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NBS

PUBLICATIONS

NBS SPECIAL PUBLICATION 260"1 1 0

U.S. DEPARTMENT OF COMMERCE/National Bureau of Standards

Standard Reference Materials:

Portland Cement Chemical

Composition Standards

(Blending, Packaging, and Testing)

QC- ft. Keith

100

U57

#260-110

1988

c-2

R. Keith Kirby and Howard M. Kanare
Tm he National Bureau of Standards' was established by an act of Congress on March 3, 1901. The Bureau's overall M goal is to strengthen and advance the nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research to assure international competitiveness and leadership of U.S.

industry, science arid technology. NBS work involves development and transfer of measurements, standards and related science and technology, in support of continually improving U.S. productivity, product quality and reliability, innovation and underlying science and engineering. The Bureau's technical work is performed by the National Measurement

Laboratory, the National Engineering Laboratory, the Institute for Computer Sciences and Technology, and the Institute for Materials Science and Engineering.

The National Measurement Laboratory

Provides the national system of physical and chemical measurement;

coordinates the system with measurement systems of other nations and

furnishes essential services leading to accurate and uniform physical and

chemical measurement throughout the Nation's scientific community,

industry, and commerce; provides advisory and research services to other Government agencies; conducts physical and chemical research; develops, produces, and distributes Standard Reference Materials; provides

calibration services; and manages the National Standard Reference Data

System. The Laboratory consists of the following centers:

• Basic Standards2 • Radiation Research

• Chemical Physics

• Analytical Chemistry

The National Engineering Laboratory

Provides technology and technical services to the public and private sectors

to address national needs and to solve national problems; conducts research

in engineering and applied science in support of these efforts; builds and

maintains competence in the necessary disciplines required to carry out this research and technical service; develops engineering data and measurement

capabilities; provides engineering measurement traceability services; develops test methods and proposes engineering standards and code

changes; develops and proposes new engineering practices; and develops and improves mechanisms to transfer results of its research to the ultimate

user. The Laboratory consists of the following centers:

Applied Mathematics

Electronics and Electrical Engineering2 Manufacturing Engineering

Building Technology

Fire Research Chemical Engineering3

The Institute for Computer Sciences and Technology

Conducts research and provides scientific and technical services to aid Federal agencies in the selection, acquisition, application, and use of computer technology to improve effectiveness and economy in Government

operations in accordance with Public Law 89-306 (40 U.S.C. 759),

relevant Executive Orders, and other directives; carries out this mission by

managing the Federal Information Processing Standards Program,

developing Federal ADP standards guidelines, and managing Federal

participation in ADP voluntary standardization activities; provides scientific and technological advisory services and assistance to Federal agencies; and

provides the technical foundation for computer-related policies of the Federal Government. The Institute consists of the following divisions:

Information Systems Engineering Systems and Software Technology Computer Security System and Network

Architecture Advanced Systems

The Institute for Materials Science and Engineering

Conducts research and provides measurements, data, standards, reference

materials, quantitative understanding and other technical information fundamental to the processing, structure, properties and performance of

materials; addresses the scientific basis for new advanced materials technologies; plans research around cross-cutting scientific themes such as nondestructive evaluation and phase diagram development; oversees Bureau-wide technical programs in nuclear reactor radiation research and

nondestructive evaluation; and broadly disseminates generic technical information resulting from its programs. The Institute consists of the following Divisions:

Ceramics

Fracture and Deformation3 Polymers

Metallurgy

Reactor Radiation

'Headquarters and Laboratories at Gaithersburg, MD, unless otherwise noted; mailing address

Gaithersburg, MD 20899.

2 Some divisions within the center are located at Boulder, CO 80303.

3 Located at Boulder, CO, with some elements at Gaithersburg, MD
Research Information Center

National bureau of Standards Standard Reference Materials:

Portland Cement Chemical

Composition Standards

(Blending, Packaging,

and Testing)

R. Keith Kirby (Retired)

Office of Standard Reference Materials

National Measurement Laboratory

National Bureau of Standards

Gaithersburg, MD 20899

and

Howard M. Kanare

Construction Technology Laboratories

Division of the Portland Cement Association

Skokie, IL 60077

U.S. DEPARTMENT OF COMMERCE, C. William Verity, Secretary NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director

Issued February 1988
Library of Congress Catalog Card Number: 88-600503

National Bureau of Standards Special Publication 260-110

Natl. Bur. Stand. (U.S.), Spec. Publ. 260-110, 103 pages (Feb. 1988)

CODEN:XNBSAV

U.S. GOVERNMENT PRINTING OFFICE WASHINGTON: 1988

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402-9325
TABLE OF CONTENTS

Introduction 1 SRMs 177, 1011, 1013, 1014, 1015, and 1016 2 SRMs 633 through 639 4 General Analytical Techniques 11 SRMs 1880 and 1881 23 Conclusions 34 Acknowledgements 36 References 37 Appendix A 38 Appendix B 63 Appendix C 70 Appendix D 75 Appendix E 77 Appendix F 79 Appendix G 82

LIST OF TABLES

1. Portland Cement SRMs 4

2. Results of the Homogeneity Tests on the "600 Series" SRMs 9

3. Results of the Analyses of Si02 12

4. Results of the Analyses of "R2O3" Group 13

5. Results of the Analyses of Fe203 14

6. Results of the Analyses of Ti02 14

7. Results of the Analyses of P2O5 14

8. Results of the Analyses of ZnO 15

9. Results of the Analyses of Cr203 15

10. Results of the Analyses of AI2O3 16

11. Results of the Analyses of Mn203 17

12. Results of the Analyses of the Calcium Group 17

13. Results of the Analyses of SrO 18

14. Results of the Analyses of MgO 19

15. Results of the Analyses of CaO 19

16. Results of the Analyses of SO3 20

17. Results of the Analyses of K20 20

18. Results of the Analyses of Na2 0 20

19. Results of the Analyses of Fluoride 21

20. Results of the Analyses of Ignition Loss 21

21. Final Results for the "600 Series" SRMs 22

22. Homogeneity of Blended Cements, SRM 1880 24

23. Prepackaging Homogeneity of SRM 1880 25

24. Results of the Analyses of Si0 2 27

25. Results of the Analyses of the "R2O3" Group 28

26. Results of the Analyses of Fe 2 03 28

27. Results of the Analyses of Ti02 29

iii
28. Results of the Analyses of P2O5 29

29. Results of the Analyses of AI2O3 29

30. Results of the Analyses of Mn203 30

31. Results of the Analyses of the Calcium Group 30

32. Results of the Analyses of SrO 30

33. Results of the Analyses of MgO 31

34. Results of the Analyses of CaO 31

35. Results of the Analyses of SO3 31

36. Results of the Analyses of K20 32

37. Results of the Analyses of Na20 32

38. Results of the Analyses of Fluoride 32

39. Results of the Analyses of Chloride 32 40. Results of the Analyses of Ignition Loss 33 41. Final Results for SRMs 1880 and 1881 33 C-l Summary of the Cooperative Test Program on the "600 Series" SRMs 72 F-l Blaine Surface Area 80 F-2 Chemical Analysis of the SRM 1880 Cements

Before Blending 80 G-l Description of Flexible Packages as Received 84 G-2 Appearance of Packages After Tests 85 G-3 Effect of High Humidity 86 G-4 Effect of CO2 Atmosphere 86 G-5 Effect of Hot Environment 87 LISTS OF FIGURES

1. Relative values for many of the constituents of SRMs 177, 1011, 1013 through 1016, 633 through 639, 1880, and 1881 3 2. Sieving one of the "600 series" portland cements 5

3. Blending one of the "600 series" portland cements 5 4. Placing vials in a tray before with cement 6

5. Capping filled vials 7 6. Flame sealing the outer glass vials 8

7. Flow sheet for the definitive analyses of the "600 series" SRMs 11

8. Scheme for mixing and blending SRM 1881 26 E-l Packing case for SRMs 1880 and 1881 78 F-l Results of particle size analysis of SRMs 1880 and 1881 81 G-l Schematic of typical laminated film 82

iv
Preface

Standard Reference Materials (SRM's) as defined by the National

Bureau of Standards (NBS) are well-characterized materials, produced in quantity and certified for one or more physical or chemical properties.

They are used to assure the accuracy and compatibility of measurements

throughout the Nation. SRM's are widely used as primary standards in many diverse fields in science, industry, and technology, both within the United States and throughout the world. They are also used extensively

in the fields of environmental and clinical analysis. In many

applications, traceability of quality control and measurement processes

to the national measurement system is carried out through the mechanism

and use of SRM's. For many of the Nation's scientists and technologists,

it is therefore of more than passing interest to know the details of the measurements made at NBS in arriving at the certified values of the SRM's produced. An NBS series of papers, of which this publication is a member, called the NBS Special Publication - 260 Series , is reserved for this purpose.

The 260 Series is dedicated to the dissemination of information on different phases of the preparation, measurement, certification, and use of NBS SRM's. In general, much more detail will be found in these papers

than is generally allowed, or desirable, in scientific journal articles.

This enables the user to assess the validity and accuracy of the measurement processes employed, to judge the statistical analysis, and to learn details of techniques and methods utilized for work entailing

greatest care and accuracy. These papers also should provide sufficient

additional information not found on the certificate so that new

applications in diverse fields not foreseen at the time the SRM was originally issued will be sought and found. Inquiries concerning the technical content of this paper should be directed to the author(s) . Other questions concerned with the availability, delivery, price, and so forth, will receive prompt

attention from: Office of Standard Reference Materials

National Bureau of Standards Gaithersburg, MD 20899

Stanley D. Rasberry, Chief

Office of Standard Reference Materials

v
OTHER NBS

Seward, R. W., ed., NBS Standard Reference Materials Catalog 1988-89, NBS Spec. Publ. 260 (January 1988)

Michaelis, R. E., and Wyman, L. L., Standard Reference Materials: Preparation of White Cast Iron

Spectrochemical Standards, NBS Misc. Publ. 260-1

(June 1964). COM74-11061**

Michaelis, R. E., Wyman, L. L., and Flitsch, R., Standard Reference Materials: Preparation of NBS Copper- Base Spectrochemical Standards, NBS Misc. Publ. 260-2 (October 1964). COM74-11063**

Michaelis, R. E., Yakowitz, H., and Moore, G. A., Stan- dard Reference Materials: Metallographic Characterization of an NBS Spectrometric Low-Alloy Steel Standard, NBS Misc. Publ. 260-3 (October 1964). COM74-11060**

Alvarez, R., and Flitsch, R., Standard Reference Materials: Accuracy of Solution X-Ray

Spectrometric Analysis of Copper-Base Alloys, NBS

Misc. Publ. 260-5 (March 1965). PB 168068**

Shultz, J. I., Standard Reference Materials: Methods for the Chemical Analysis of White Cast Iron Standards, NBS Misc. Publ. 260-6 (July 1965). COM74-

11068**

Bell, R. K., Standard Reference Materials: Methods for the Chemical Analysis of NBS Copper-Base

Spectrochermical Standards, NBS Misc. Publ. 260-7

(October 1965). COM74- 11067** Richmond, M. S., Standard Reference Materials: Analysis of Uranium Concentrates at the National Bureau of Standards, NBS Misc. Publ. 260-8 (December 1965). COM74-11066**

Anspach, S. C, Cavallo, L. M., Garfinkel, S. B., Hutchinson, J. M. R., and Smith, C. N., Standard Reference Materials: Half Lives of Materials Used in the Preparation of Standard Reference Materials of Nineteen Radioactive Nuclides Issued by the National Bureau of Standars, NBS Misc. Publ. 260-9 (November 1965). COM74-11065**

Yakowitz, H., Vieth, D. L., Heinrich, K. F. J., and

Michaelis, R. E., Standard Reference Materials: Homogeneity Characterization ofNBS Spectrometric Standards II: Cartridge Brass and Low-Alloy Steel, NBS Misc. Publ. 260-10 (December 1965). COM74-

11064**

Napolitano, A., and Hawkins, E. G., Standard Reference

Materials: Viscosity of Standard Lead-Silica Glass, NBS Misc. Publ. 260-1 1 (November 1966).

IN THIS SERIES

Yakowitz, H., Vieth, D. L., and Michaelis, R. E., Stan- dard Reference Materials: Homogeneity Characterization of NBS Spectrometric Standards III: White

Cast Iron and Stainless Steel Powder Compact, NBS

Misc. Publ. 260-12 (September 1966). Menis, O., and Sterling, J. T., Standard Reference

Materials: Determination of Oxygen in Ferrous Materials—SRM 1090, 1091, and 1092, NBS Misc.

Publ. 260-14 (September 1966). Yakowitz, H., Michaelis, R. E., and Vieth, D. L., Stan- dard Reference Materials: Homogeneity Characterization of NBS Spectrometric Standards IV:

Preparation and Microprobe Characterization of W20% Mo Alloy Fabricated by Powder Metallurgical Methods, NBS Spec. Publ. 260-16 (January 1969). COM74-11062**

Paule, R. C, and Mandel, J., Standard Reference

Materials: Analysis of Interlaboratory Measurements on the Vapor Pressure of Gold (Certification of Stan- dard Reference Material 745). NBS Spec. Publ. 260-

19 (January 1970). PB190071**

Paule, R. C, and Mandel, J., Standard Reference

Materials: Analysis of Interlaboratory Measurements on the Vapor Pressures of Cadmium and Silver, NBS

Spec. Publ. 260-21 (January 1971). COM74-1 1359**

Yakowitz, H., Fiori, C. E., and Michaelis, R. E., Stan- dard Reference Materials: Homogeneity Characterization of Fe-3 Si Alloy, NBS Spec. Publ. 260-22

(February 1971). COM74-11357**

Napolitano, A., and Hawkins, E. G., Standard Reference

Materials: Viscosity of a Standard Borosilicate Glass, NBS Spec. Publ. 260-23 (December 1970). COM71-

00157**

Sappenfield, K. M., Marinenko, G., and Hague, J. L., Standard Reference Materials: Comparison of Redox

Standards, NBS Spec. Publ. 260-24 (January 1972). COM72-50058**

Hicho, G. E., Yakowitz, H., Rasberry, S. D., and

Michaelis, R. E., Standard Reference Materials: A

Standard Reference Material Containing Nominally Four Percent Austenite, NBS Spec. Publ. 260-25

(February 1971). COM74-11356**

Martin, J. F., Standard Reference Materials: National Bureau of Standards-US Steel Corporation Joint Prognam for Determining Oxygen and Nitrogen in Steel, NBS Spec. Publ. 260-26 (February 1971). PB

81176620**

Garner, E. L., Machlan, L. A., and Shields, W. R., Stan- dard Reference Materials: Uranium Isotopic Standard Reference Materials, NBS Spec. Publ. 260-27 (April 1971). COM74-1 1358**

vi
Heinrich, K. F. J., Myklebust, R. L., Rasberry, S. D., and

Michaelis, R. E., Standard Reference Materials: Preparation and Evaluation of SRM's 481 and 482 Gold-Silver and Gold-Copper Alloys for

Microanalysis, NBS Spec. Publ. 260-28 (August

1971). COM71-50365**

Geller, S. B., Standard Relerence Materials: Calibration of NBS Secondary Standard Magnetic Tape (Computer Amplitude Reference) Using the Reference Tape Amplitude Measurement "Process A-Model

2," NBS Spec. Publ. 260-29 (June 1971). COM71-

50282**

Gorozhanina, R. S., Freedman, A. Y., and Shaievitch, A.

B. (translated by M. C. Selby), Standard Reference

Materials: Standard Samples Issued in the USSR (A

Translation from the Russian), NBS Spec. Publ. 260- 30 (June 1971). COM71-50283**

Hust, J. G., and Sparks, L. L., Standard Reference

Materials: Thermal Conductivity of Electrolytic Iron SRM 734 from 4 to 300 K, NBS Spec. Publ. 260-31 (November 1971). COM71-50563**

Mavrodineanu, R., and Lazar, J. W., Standard Reference

Materials: Standard Quartz Cuvettes for High Accuracy Spectrophotometry, NBS Spec. Publ. 260-32 (December 1973). COM74-50018**

Wagner, H. L., Standard Reference Materials: Comparison of Original and Supplemental SRM 705, Nar- row Molecnlar Weight Distribution Polystyrene, NBS Spec. Publ. 260-33 (May 1972). COM72-

50526**

Sparks, L. L., and Hust, J. G., Standard Reference

Materials: Thermal Conductivity of Austenitic Stainless Steel, SRM735 from 5 to 280 K, NBS Spec. Publ. 260-35 (April 1972.) COM72-50368**

Cali, J. P., Mandel, J., Moore, L. J., and Young, D. S., Standard Reference Materials: A Referee Method for the Determination of Calcium in Serum NBS SRM

915, NBS Spec. Publ. 260-36 (May 1972). COM72-

50527**

Shultz, J. I., Bell, R. K., Rains, T. C, and Menis, O., Stan- dard Reference Materials: Methods of Analysis of NBS Clay Standards, NBS Spec. Publ. 260-37 (June 1972). COM72-50692**

Clark, A. F., Denson, V. A., Hust, J. G., and Powell, R.

L., Standard Reference Materials: The Eddy Current Decay Method for Resistivity Characterization of

High-Purity Metals, NBS Spec. Publ. 260-39 (May

1972). COM72-50529**

McAdie, H. G., Garn, P. D., and Menis, O., Standard Reference Materials: Selection of Thermal Analysis Termperature Standards Through a Cooperative

Study (SRM 758, 759, 760), NBS Spec. Publ. 260-40

(August 1972) COM72-50776**

Wagner, H. L., and Verdier, P. H., eds., Standard

Reference Materials: The Characterization of Linear

Polyethylene, SRM 1475, NBS Spec. Publ. 260-42

(September 1972). COM72-50944**

Yakowitz, H., Ruff, A. W., and Michaelis, R. E., Stan- dard Reference Materials: Preparation and

Homogeneity Characterization of an Austenitic Iron- Chromium-Nickel Alloy, NBS Spec. Publ. 260-43 (November 1972). COM73-50760**

Schooley, J. F., Soulen, R. J., Jr., and Evans, G. A., Jr., Standard Reference Materials: Preparation and Use

of Superconductive Fixed Point Devices, SRM 767, NBS Spec. Publ. 260-44 (December 1972). COM73-

50037**

Greifer, B., Maienthal, E. J., Rains, T. C, and Rasberry,

S. D., Standard Reference Materials: Powdered Lead- Based Paint, SRM 1579, NBS Spec. Publ. 260-45 (March 1973). COM73-50226**

Hust, J. G., and Giarratano, P. J., Standard Reference

Materials: Thermal Conductivity and Electrical

Resistivity Standard Reference Materials: Austenitic

Stainless Steel, SRM's 735 and 798, from 4 to 1200 K, NBS Spec. Publ. 260-46 (March 1975). COM75-

10339**

Hust, J. G., Standard Reference Materials: Electrical Resistivity of Electrolytic Iron, SRM 797, and Austenitic Stainless Steel, SRM 798, from 5 to 280 K, NBS Spec. Publ. 260-47 (February 1974). COM74-

50176** Mangum, B. W., and Wise, J. A., Standard Reference

Materials: Description and Use of Precision Ther- mometers for the Clinical Lahoratory, SRM 933 and SRM 934, NBS Spec. Publ. 260-48 (May 1974). COM74-50533**

Carpenter, B. S., and Reimer, G. M., Standard Reference

Materials: Calibrated Glass Standards for Fission Track Use, NBS Spec. Publ. 260-49 (November

1974). COM74-51 185**

Hust, J. G., and Giarratano, P. J., Standard Reference

Materials: Thermal Conductivity and Electrical

Resistivity Standard Reference Materials: Electrolytic Iron, SRM's 734 and 797 from 4 to 1000 K, NBS

Spec. Publ. 260-50 (June 1975). COM75- 10698** Mavrodineanu, R., and Baldwin, J. R., Standard

Reference Materials: Glass Filters As a Standard Reference Material for Spectrophotometry-Selec

tion, Preparation, Certification, Use-SRM 930 NBS

Spec. Publ. 260-51 (November 1975). COM75-

10339**

Hust, J. G., and Giarratano, P. J., Standard Reference

Materials: Thermal Conductivity and Electrical

Resistivity Standard Reference Materials 730 and

799, from 4 to 3000 K, NBS Spec. Publ. 260-52 (Sep- tember 1975). COM75-11193**

Durst, R. A., Standard Reference Materials: Standardization of pH Measurements, NBS Spec. Publ. 260- 53 (December 1975, Revised). PB248127**

vii
Burke, R. W., and Mavrodineanu, R., Standard

Reference Materials: Certification and Use of Acidic Potassium Dichromate Solutions as an Ultraviolet Absorbance Standard, NBS Spec. Publ. 260-54

(August 1977).PB272168**

Ditmars, D. A., Cezairliyan, A., Ishihara, S., and

Douglas, T. B., Standard Reference Materials: Enthalpy and Heat Capacity; Molybdenum SRM 781, from 273 to 2800 K, NBS Spec. Publ. 260-55 (Sep- tember 1977). PB272127**

Powell, R. L., Sparks, L. L., and Hust, J. G., Standard Reference Materials: Standard Thermocouple

Material, Pt-67: SRM 1967, NBS Spec. Publ. 260-56

(February 1978). PB277 172**

Barnes, J. D., and Martin, G. M., Standard Reference

Materials: Polyester Film for Oxygen Gas Transmission Measurements SRM 1470, NBS Spec. Publ. 260- 58 (June 1979). PB297098**

Velapoldi, R. A., Paule, R. C, Schaffer, R., Mandel, J., and Moody, J. R., Standard Reference Materials: A

Reference Method for the Determination of Sodium

in Serum, NBS Spec. Publ. 260-60 (August 1978). PB286944**

Verdier, P H., and Wagner, H. L., Standard Reference Materials: The Characterization of Linear

Polyethylene (SRM 1482, 1483, 1484), NBS Spec.

Publ. 260-61 (December 1978). PB289899**

Soulen, R. J., and Dove, R. B., Standard Reference

Materials: Temperature Reference Standard for Use Below 0.5 K (SRM 768), NBS Spec. Publ. 260-62

(April 1979). PB294245**

Velapoldi, R. A., Paule, R. C, Schaffer, R., Mandel, J., Machlan, L. A., and Gramlich, J. W., Standard

Reference Materials: A Reference Method for the Determination of Potassium in Serum, NBS Spec.

Publ. 260-63 (May 1979). PB297207**

Velapoldi, R. A., and Mielenz, K. D., Standard Reference Materials: A Fluorescence Standard

Reference Material Quinine Sulfate Dihydrate (SRM

936), NBS Spec. Publ. 260-64 (January 1980). PB80-

132046**

Marinenko, R. B., Heinrich, K. F. J., and Ruegg, F. C,

Standard Reference Materials: Micro-Homogeneity

Studies of NBS Standard Reference Materials, NBS

Research Materials, and Other Related Samples, NBS

Spec. Publ. 260-65 (September 1979). PB300461**

Venable, W. H., Jr., and Eckerle, K. L., Standard Reference Materials: Didymium Glass Filters for Calibrating the Wavelength Scale of

Spectrophotometers-SRM 2009, 2010, 2013, and

2014, NBS Spec. Publ. 260-66 (October 1979). PB80-

104961**

Velapoldi, R. A., Paule, R. C, Schaffer, R., Mandel, J., Murphy, T. J., and Gramlich, J. W., Standard

Reference Materials: A Reference Method for the Determination ofChloride in Serum, NBS Spec. Publ. 260-67 (November 1979). PB80-110117**

Mavrodineanu, R., and Baldwin, J. R., Standard

Reference Materials: Metal-On-Quartz Filters as a Standard Reference Material for Spectrophotometry SRM 2031, NBS Spec. Publ. 260-68 (April 1980). PB80-197486**

Velapoldi, R. A., Paule, R. C, Schaffer, R., Mandel, J., Machlan, L. A., Garner, E. L., and Rains, T. C, Stan- dard Reference Materials: A Reference Method for the Determination of Lithium in Serum, NBS Spec.

Publ. 260-69 (July 1980). PB80-2091 17** Marinenko, R. B., Biancaniello, F., Boyer, P. A., Ruff, A. W., and DeRobertis, L., Standard Reference

Materials: Preparation and Characterization of an Iron-Chromium-Nickel Alloy for Microanalysis, NBS Spec. Publ. 260-70 (May 1981). PB84-

165349** Seward, R. W., and Mavrodineanu, R., Standard Reference Materials: Summary of the Clinical Laboratory Standards Issued by the National Bureau

of Standards, NBS Spec. Publ. 260-71 (November

1981) .PB82-135161**

Reeder, D. J., Coxon, B., Enagonio, D., Christensen, R.

G., Schaffer, R., Howell, B. F., Paule, R. C, and Mandel, J., Standard Reference Materials: SRM 900, Antiepilepsy Drug Level Assay Standard, NBS Spec.

Publ. 260-72 (June 1981). PB81-220758

Interrante, C. G., and Hicho, G. E., Standard Reference

Materials: A Standard Reference Material Containing Nominally Fifteen Percent Austenite (SRM 486), NBS Spec. Publ. 260-73 (January 1982). PB82-

215559**

Marinenko, R. B., Standard Reference Materials:

Preparation and Characterization of K-41 1 and K-414

Mineral Glasses for Microanalysis: SRM 470, NBS

Spec. Publ. 260-74 (April 1982). PB82-221300**

Weidner, V. R., and Hsia, J. J., Standard Reference

Materials: Preparation and Calibration of First Surface Aluminum Mirror Specular Reflectance Stan- dards (SRM 2003a), NBS Spec. Publ. 260-75 (May

1982).PB82-221367**

Hicho, G. E., and Eaton, E. E., Standard Reference

Materials: A Standard Reference Material Containing Nominally Five Percent Austenite (SRM 485a), NBS

Spec. Publ. 260-76 (August 1982). PB83-1 15568**

Furukawa, G. T., Riddle, J. L., Bigge, W. G., and Pfieffer, E. R., Standard Reference Materials: Application of Some Metal SRM's as Thermometric Fixed Points, NBS Spec. Publ. 260-77 (August 1982). PB83-

117325**

Hicho, G. E., and Eaton, E. E., Standard Reference

Materials: Standard Reference Material Containing Nominally Thirty Percent Austenite (SRM487), NBS

Spec. Publ. 260-78 (September 1982). PB83-

115576**

viii
Richmond, J. C, Hsia, J. J., Weidner, V. R., and Wilmering, D. B., Standard Reference Materials: Second

Surface Mirror Standards of Specular Spectral Reflectance (SRM's 2023, 2024, 2025), NBS Spec.

Publ. 260-79 (October 1982). PB84-203447**

Schaffer, R., Mandel, J., Sun, T., Cohen, A., and Hertz, H. S., Standard Reference Materials: Evaluation by

an ID/MS Method of the AACC Reference Method

for Serum Glucose, NBS Spec. Publ. 260-80 (October

1982).PB84-216894**

Burke, R. W., and Mavrodineanu, R., Standard Reference Materials: Accuracy in Analytical

Spectrophotometry, NBS Spec. Publ. 260-81 (April 1983). PB83-214536**

Weidner, V. R., Standard Reference Materials: White

Opal Glass Diffuse Spectral Reflectance Standards

for the Visible Spectrum (SRM's 2015 and 2016), NBS Spec. Publ. 260-82 (April 1983). PB83-

220723**

Bowers, G. N., Jr., Alvarez, R., Cali, J. P., Eberhardt, K.

R., Reeder, D. J., Schaffer, R., and Uriano, G. A., Standard Reference Materials: The Measurement of

the Catalytic (Activity) Concentration of Seven En- zymes in NBS Human Serum SRM 909, NBS Spec.

Publ. 260-83 (June 1983). PB83-239509**

Gills, T. E., Seward, R. W., Collins, R. J., and Webster, W. C, Standard Reference Materials: Sampling,

Materials Handling, Processing, and Packaging of NBS Sulfur in Coal Standard Reference Materials 2682, 2683, 2684, and 2685, NBS Spec. Publ. 260-84

(August 1983). PB84-109552**

Swyt, D. A., Standard Reference Materials: A Look at Techniques for the Dimensional Calibration of Stan- dard Microscopic Particles, NBS Spec. Publ. 260-85

(September 1983). PB84-1 12648**

Hicho, G. E., and Eaton, E. E., Standard Reference

Materials: A Standard Reference Material Containing Two and One-Half Percent Austenite, SRM 488, NBS Spec. Publ. 260-86 (December 1983). PB84-

143296** Mangum, B. W., Standard Reference Materials: SRM

1969: Rubidium Triple-Point - A Temperature

Reference Standard Near 39.30 °C, NBS Spec. Publ. 260-87 (December 1983). PB84-149996**

Gladney, E. S., Burns, C. E., Perrin, D. R., Roelandts, I., and Gills, T. E., Standard Reference Materials: 1982

Compilation of Elemental Concentration Data for NBS Biological, Geological, and Environmental

Standard Reference Materials, NBS Spec. Publ. 260- 88 (March 1984). PB84-218338**

Hust, J. G., Standard Reference Materials: A Fine- Grained, Isotropic Graphite for Use as NBS Ther- mophysical Property RM's from 5 to 2500 K, NBS

Spec. Publ. 260-89 (September 1984). PB85-

112886**

Hust, J. G., and Lankford, A. B., Standard Reference

Materials: Update of Thermal Conductivity and

Electrical Resistivity of Electrolytic Iron, Tungsten, and Stainless Steel, NBS Spec. Publ. 260-90 (Sep- tember 1984). PB85-1 15814**

Goodrich, L. F., Vecchia, D. F., Pittman, E. S., Ekin, J. W., and Clark, A. F., Standard Reference Materials:

Critical Current Measurements on an NbTi Superconducting Wire Standard Reference Material, NBS

Spec. Publ. 260-91 (September 1984). PB85-

118594**

Carpenter, B. S., Standard Reference Materials:

Calibrated Glass Standards for Fission Track Use

(Supplement to NBS Spec. Publ. 260-49), NBS Spec.

Publ. 260-92 (September 1984). PB85-1 13025**

Ehrstein, J.R., Standard Reference Materials: Preparation and Certification of Standard Reference

Materials for Calibration of Spreading Resistance

Probes, NBS Spec. Publ. 260-93 (January 1985). PB85-177921**

Gills, T. E., Koch, W. F., Stolz, J. W., Kelly, W. R., Paulsen, P. J., Colbert, J. C, Kirklin, D. R., Pei, P.T.S., Weeks, S., Lindstrom, R. M., Fleming, R. F., Greenberg, R. R., and Paule, R. C, Standard Reference

Materials: Methods and Procedures Used at the National Bureau of Standards to Certify Sulfur in Coal SRM's for Sulfur Content, Calorific Value, Ash Content, NBS Spec. Publ. 260-94 (December 1984). PB85-165900**

Mulholland, G. W., Hartman, A. W., Hembree, G. G., Marx, E., and Lettieri, T. R„ Standard Reference

Materials: Development of a 1 |jm Diameter Particle Size Standard, SRM 1690, NBS Spec. Publ. 260-95 (May 1985). SN003-003-02665-4*

Carpenter, B. S., Gramlich, J. W., Greenberg, R. R., Machlan, L. A., DeBievre, P., Eschbach, H. L., Meyer, H, Van Audenhove, J., Connolly, V. E., Trahey, N. M., and Zook, A. C, Standard Reference

Materials: Unanium-235 Isotopic Abundance Stan- dard Reference Materials for Gamma Spectrometry Measurements, NBS Spec. Publ. 260-% (September

1986). PB87- 108544**

Mavrodineanu, R., and Gills, T. E., Standard Reference

Materials: Summary of the Coal, Ore, Mineral, Rock, and Refactory Standards Issued by the National Bureau of Standards, NBS Spec. Publ. 260-97 (Sep- tember 1985). SN003-003-02688-3*

Hust, J. G., Standard Reference Materials: Glass Fiber- board SRM for Thermal Resistance, NBS Spec. Publ. 260-98 (August 1985). SN003-003-02674-3*

Callanan, J. E., Sullivan, S. A., and Vecchia, D. F., Stan- dard Reference Materials: Feasibility Study for the Development of Standards Using Differential Scanning Calorimetry, NBS Spec. Publ. 260-99 (August

1985). SN003-003-02675-1*

ix
Taylor, J. K., Standard Reference Materials: Handbook

for SRM Users, NBS Spec. Publ. 260-100 (September 1985). PB86-1 10897** Mangum, B. W., Standard Reference Materials: SRM

1970, Succinonitrile Triple-Point Standard: A

Temperature Reference Standard Near 58.08 °C, NBS

Spec. Publ. 260-101 (March 1986). SN003-003-

02722-7*

Weidner, V. R., Mavrodineanu, R., Mielenz, K. D., Velapoldi, R. A., Eckerle, K. L., and Adams, B., Stan- dard Reference Materials: Holmium Oxide Solution Wavelength Standard from 240- 650 nm, SRM 2034, NBS Spec. Publ. 260-102 (July 1986). PB86-

245727**

Hust, J. G., Standard Reference Materials: Glass

Fiberblanket SRM for Thermal Resistance, NBS

Spec. Publ. 260-103 (September 1985). SN003-003-

02687-5*

Mavrodineanu, R., and Alvarez, R., Standard Reference

Materials: Summary of the Biological and Botanical Standards Issued by the National Bureau of Standards, NBS Spec. Publ. 260-104 (November 1985). SN003-003-02704-9* Mavrodineanu, R., and Rasberry, S. D., Standard

Reference Materials: Summary of the Environmental

Research, Analysis, and Control Standards Issued by

the National Bureau of Standards, NBS Spec. Publ. 260-105 (March 1986). SN003-003-02725-1* Koch, W. F., ed., Standard Reference Materials: Methods and Procedures Used at the National Bureau

of Standards to Prepare, Analyze, and Certify SRM

2694, Simulated Rainwater, and Recommendations

for Use, NBS Spec. Publ. 260-106 (July 1986). PB86-

247483**

Hartman, A. W., Standard Reference Materials: SRM

1965, Microsphere Slide (10 |im Polystyrene

Spheres), NBS Spec. Publ. 260-107 (In Preparation). Mavrodineanu, R., and Gills, T. E., Standard Reference

Materials: Summary of Gas Cylinder and Permeation Tube Standard Reference Materials Issued by the National Bureau of Standards, NBS Spec. Publ. 260-108 (May 1987). Candela, G. A., Chandler-Horowitz, D., Novotny, D. B., Marchiando, J. F., and Belzer, B. J., Standard

Reference Materials: Preparation and Certification of

an Ellipsometrically Derived Thickness and Refractive Index Standard of a Silicon Dioxide Film (SRM

2530), NBS Spec. Publ. 260-109 (In Preparation). Kirby, R. K., and Kanare, H. M., Standard Reference

Materials: Portland Cement Chemical Composition

Standards (Blending, Packaging, and Testing), NBS

Spec. Publ. 260-110

Gladney, E. S., O'Malley, B. T., Roelandts, L, and Gills, T. E., Standard Reference Materials: Compilation of Elemental Concentration Data for NBS Clinical, Biological, Geological, and Environmental Standard Reference Materials, NBS Spec. Publ. 260-111 (November 1987). *Send order with remittance to Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20102. Remittance from foreign countries should include an additional one fourth of

the purchase price for postage. **May be ordered from: National Technical Information Services (NTIS), Springfield, VA 22161.

x
INTRODUCTION

The portland cement Standard Reference Materials (SRMs) are primarily intended

for use in the calibration of instrumental methods used in the chemical

analysis of commercial portland cements. When necessary, these SRMs can also

be used to check the determination of major component concentrations (silica,

alumina, calcium oxide, and magnesia) by classical chemical methods.

The National Bureau of Standards (NBS) produced the first portland cement standard (SRM 177) in 1958. To meet the needs of the cement industry's growing

use of instrumental methods of analysis, such as x-ray fluorescence and atomic

absorption, a series of five standards (SRMs 1011, 1013, 1014, 1015, and 1016) was made available in 1962. When this supply was exhausted, it was replaced by

a new series of seven standards (SRMs 633 through 639) which became available

in 1973. A provisional certificate for these seven SRMs was based on a cooperative test program in which 14 laboratories participated, including NBS and the Portland

Cement Association (PCA) . Although eight of these laboratories used "wet chemistry" for the major constituents (NBS measurements were made by x-ray

fluorescence) , none of the tests achieved the measurement precision achieved by

NBS and PCA on the previous series of five SRMs. Accordingly, in 1974 NBS placed a contract with PCA to perform, with the aid and consultation of the Erlin, Hine Associates, a "definitive analyses" of the seven standards. These analyses resulted in the final certification in 1977. In 1981 a questionnaire was distributed by the American Society for Testing and Materials (ASTM) to the members of its committee on cement, ASTM Committee C-l, to solicit suggestions for the chemical composition of two new SRMs. The majority of nearly 50 responses to the questionnaire indicated that there was a need to fill in some blank areas in the ranges for some constituents, such as SO3 , and to extend the range for some constituents, such as K2O. Under

contract to NBS, the PCA proceeded to obtain, blend, package, and analyze these standards. Subsequently, SRMs 1880 and 1881 were certified in 1982 and 1983,

respectively

.

The purpose of this paper is to present a detailed description of the blending,

packaging, testing, and characterization of the portland cement SRMs.

1
SRMs 177, 1011, 1013, 1014, 1015, and 1016 While most of the information on these standards was not fully documented, the following facts are known: The cements were selected on the basis of analyses

conducted at NBS by B. Leonard Bean of the Inorganic Building Materials Section

and were packaged in essentially the same manner as at present -- i . e ., the samples were placed in stoppered glass vials and then flame sealed in outer

glass vials. Each of these standards took several days to vial with the possible result that the water content may have changed between the initial and

final vialed units due to changes in the ambient relative humidity. This may have caused the larger- than-usual variation of the loss-on- ignition values. Cooperative testing programs provided the data for certification. In the case for SRM 177, thirteen laboratories provided the analyses while ten laboratories

provided analyses in the "1000 series". In all cases, average values for the concentration of the constituents were used for the certification, but only after a careful technical and statistical analysis eliminated some values. It

is interesting to note that the certificates for the "1000 series" SRMs were "provisional" which meant that there may have been some doubt about the average values

Figure 1 presents values for many of the constituents of the portland cement

standards. Copies of the certificates are shown in Appendix A.

2
SRM 1880. 1881 SRM 633-630 SRM 1011-1016

SRM 1880. 1881 SRM 633-639SRM 1011-1016

58 59 60 61 62 63 64 65 66 67

Percent CaO

20 21 22 23 24 25

Percent Si02

SRM 1880. 1881 SRM 633-639

SRM 1880. 1881 SRM 633-639 SRM 1011-1016 -O—O OSRM 1011-1016

Percent Fe203

SRM 1880. 1881 SRM 633-639

SRM 1880. 1881 SRM 633-639 SRM 1011-1016

Percent AI203

O O O SRM 1011-1016

. SRM 177

SRM 1880. 1881

SRM 633-639

SRM 177

SRM 1011-1016

SRM 1880, 1881

o—o—o- « SRM 177

SRM 633-639 SRM 1011-1016

0.0 0.2 Percent K20

0.0 0 1

SRM 1880. 1881

O O-O-O O SRM 1011-1016

SRM 633-639

1.5 Z0

Percent Loss-on-lgnitio

Figure 1. Relative values for many of the constituents of SRMs 177 1011, 1013 through 1016, 633 through 639, 1880, and 1881

3
SRMs 633 THROUGH 639 With the approaching depletion of stock of the "1000 series", it became necessary to select cements for the replacement series of standards. Accordingly, a letter was sent to all cement producers requesting information

on the chemical composition of portland cements currently being produced.

Response to this letter was favorable but unfortunately either most of the plants had no information on minor constituents or in some cases the information supplied was unreliable. The information was sufficient, however,

to allow Bruce Foster of the NBS Cement and Concrete Research Laboratory to select seven cements, see Table 1, including an expansive type portland cement. White cements were ruled out because of their virtual absence of iron. Table 1. Portland Cement SRMs Percent by Weight

SRM CaO Si0 2 A1 2 Q3 Fe.20-3 S0 3 MgQ SrO TiOo K2O Na2 Q Loss

177 64 2 21 9 5 3 2 4 1 6 2. 4. 0 2 0 3 0 6 0 1 1.2 1011 66 6 21 0 5 4 2 1 1 8 1. 1 0 1 0 2 0 3 0 1 1.1 1013 64 3 24 2 3 3 3 1 1 8 1. 4 0 1 0 2 0 3 0 2 1.0 1014 63 4 19 5 6 4 2 5 2 7 2. 8 0 3 0 2 1 0 0 2 0.8 1015 61 5 20 6 5 0 3 3 2 3 4. 2 0 1 0 3 0 9 0 2 1.7 1016 65 3 21 0 5 0 3 7 2 3 0 4 0 2 0 3 0 0 0 6 1.2

633 64 5 21 9 3 8 4 2 2 2 1 0 0 3 0 2 0 2 0 6 0.8 634 62 6 20 7 5 2 2 8 2 2 3 3 0 1 0 3 0 4 0 2 1.6 635 59 8 18 4 6 3 2 6 7 1 1 2 0 2 0 3 0 4 0 1 3.2 636 63 5 23 2 3 0 1 6 2 3 4 0 0 0 0 2 0 6 0 1 1.2 637 66 0 23 1 3 3 1 8 2 4 0 7 0 1 0 2 0 2 0 2 1.7 638 62 1 21 5 4 4 3 6 2 3 3 8 0 1 0 2 0 6 0 1 1.0

639 65 8 21 6 4 3 2 4 2 5 1 3 0 2 0 3 0 1 0 6 1.0 1880 63 1 19 8 5 0 2 9 3 4 2 7 0 1 0 2 0 9 0 3 1.4 1881 58 7 22 2 4 2 4 7 3 6 2 6 0 1 0 2 1 2 0 0 2.0

Three 94- lb bags of each cement were donated by the producers. Upon receipt,

the three bags of cement were sifted through a No . 50 wire -cloth sieve to remove oversize particles and to break up conglomerates (see Figure 2) . The cement was then placed in a 4 cubic-foot double-cone blender (see Figure 3) and mixed for four hours. The cement was then scooped from the blender into plastic bags so that all of the bags contained representative samples of the mixed cement. The bags were than placed in containers which were sealed and

set aside until the cement was packaged in vials.

4

Rather than fill the vials one at a time, as in the past, a technique was developed in which about 400 vials were placed in a tray (see Figure 4) filled

with cement, vibrated to settle the cement, and capped (see Figure 5.)

Figure 4. Placing vials in a tray before filling with cement.

6
Figure 5. Capping filled vials. Using this technique, the cement for one of the standards could be packaged in one day. Packaging was carried out in February when the humidity was low. The filled and capped vials were stored in 15 or 16 sealed cans until they could be flame-sealed in the outer glass vials. Flame sealing was accomplished with the automatic sealer shown in Figure 6. The homogeneity of each standard was tested by comparing the calcium and sulfur variation between two vials taken from each of the containers. The 32 specimens were prepared by briquetting and were then analyzed (repeating each measurement four times) by normal x-ray fluorescence methods. The data obtained in these tests are given in Appendix B and are summarized in Table 2. The data indicate that each of the cement standards was sufficiently

homogeneous. The reason for measuring the variations of the calcium and sulfur content is that in the production of portland cement, gypsum (which contains most of the sulfur) is added to and ground with the cement clinker (which

contains calcium, the most abundant element) to help control the setting time of the concrete. Therefore, if these elements are homogeneously distributed in the standards, it is a good indication that the mixing was complete and that

the other constituents are also uniformly distributed.

7
Figure 6. Flame sealing the outer glass vials.

As with the earlier SRMs , a cooperative test program was set up involving NBS

,

PCA, the Army Corps of Engineers, and ten cement manufactures. These 13 laboratories are listed in Appendix C along with a comparative summary of their results prepared by William G. Hine*. The methods used were primarily

instrumental with the "1000 series" used for calibration. Only two laboratories performed wet analytical procedures that were considered to be reasonably accurate, according to and using methods specified in ASTM C114,

Standard Methods for Chemical Analysis of Hydraulic Cement [1]. Even in these

* Erlin, Hine Associates

811 Skokie Boulevard

Northbrook, IL 60062

8
tests, however, corrections were not made for incomplete separations. Five other laboratories used short-cut modifications of the ASTM standard methods.

One laboratory used the Jugovic [2] method which is a combination of colorimetric and complexometric methods in which the samples are fused with

sodium hydroxide and then dissolved in hydrochloric acid. Seven laboratories,

including NBS, used x-ray fluorescence techniques in which all but one used pelletized samples. That laboratory fused the cements with lithium borate. Two laboratories used atomic absorption techniques in which the cements are fused with lithium metaborate and then dissolved in nitric acid [3]

.

Table 2. Results of the Homogeneity Tests on the "600 Series" SRMs CaO SO3. SRM n Std Dev Coef of Var Std Dev Coef of Var

633 32 0.069% by wt. 0 105% 0.015% by wt. 0.67%

634 32 0.057 0 091 0.012 0.56

635 32 0.094 0 158 0.028 0.40

636 30 0.111 0 176 0.019 0.82

637 30 0.085 0 129 0.011 0.47

638 30 0.077 0 124 0.016 0.68

639 29 0.115 0 175 0.020 0.79

The results of this cooperative test program were used for the "provisional"

certification of the "600 series" in 1974 (see Appendix C) . More than 3000 individual determinations were reported for the constituents in the seven SRMs. The certified values were obtained by a critical evaluation of the analytical methods and the reported data. Because the results of this test program did not provide the accuracy necessary to meet the needs of an ASTM method of analysis, NBS contracted with PCA (with William G. Hine acting as consultant)

to provide for the "definitive analyses" of these SRMs. For this work, wet chemistry techniques were used to provide the basic measurement of the major

components and instrumental techniques were used not only to measure the lesser components but to also determine impurity levels in the precipitates and filtrates to provide corrections for the wet chemistry results.

In general, x-ray fluorescence (XRF) and atomic absorption spectroscopy (AAS) techniques were used. The particular XRF employed allowed detection of elements of atomic number 12 (magnesium) and above with greatly varying

sensitivity. Limited experimentation with various precipitates indicated the detection limits to range from 0.4 milligram for magnesium oxide (equivalent to 0.08 percent in the SRM), to 0.2 milligram for silica (0.04 percent), to less than 0.01 milligram (0.02 percent) for elements of the fourth period of the Periodic Table of Elements. AAS was employed where the sensitivity of this technique allowed detection of 0.1 milligram (0.02 percent) of a constituent. Analyses for sodium and

potassium, for example, were frequently made by this technique. Because of its suitability for analyzing liquids, AAS was also used to examine the filtrates

from each precipitation step. By the use of standard addition techniques, it was demonstrated that a sensitivity of 0.1 milligram (0.02 percent) was achievable for the analyzed elements.

9
Finally, optical emission spectroscopy (capable of detecting elements in the parts per million or less level) was employed in a few instances (e.g., the ammonium hydroxide group precipitate of SRM 635) . This method was used as check on the XRF results.

10
GENERAL ANALYTICAL TECHNIQUES

The scheme of the analytical program is shown . in Figure 7. A 0.5-g sample was used in all cases. Newly opened vials of the SRM were used for determinations

of all the major components. For minor components, previously opened vials

were occasionally used.

SRM Cement (0.5 gram sample; decomposition and dissolution by hydrochloric acid).

FILTRATE contains remaining cement elements. Colorimctric analysis used to determine unprecipi- tated (soluble) Si0 2

in filtrate.

Double dehydration of the <

PRECIPITATE of impure Si0 2 . X-ray fluorescence (XRF) analysis used to detect i purities in the precipitate.

"HF" treatment of Si0 2 precipitate removes Si0 2 (by evolution as SiF 4 ). Residue remains (contains the impurities).

RESIDUE ignited, weighed, fused, and added

trate from dehydration.

Double precipitation of NHjOH (R 2 03 ) group

(AljOa. Fe2 03 . P2 O s . Ti02 , ZnO. Cr2 03 . and ZrO).

PRECIPITATE ignited and weighed

X-ray fluorescence analysis used t Cr2 03 , Zr and other impurities.

R 2 03 group, detect ZnO, FILTRATE contains CaO. MgO, Mn2 03 , K2 0. Na2 0. SrO,S03 .etc.) Atomic absorption analysis used to detect unprecipitated Al2 0 3 and Fe2 0 3 .

Removal of manganese (by co-precipitation method of Peck) prior to the calcium group determination.

PRECIPITATE of Mn02 discarded. No XRF analysis for impurities performed because

precipitate was too small.

FILTRATE (contains CaO, MgO, K2 0. Na2 0. S0 3 . etc.) Atomic absorption analysis used to detect unprecipitated manganese.

Double precipitation of calcium group (CaO and SrO) with ammonium oxalate.

PRECIPITATE ignited and weighed as CaO and SrO. Atomic absorption analysis used to determine the tof SrO in precipitate.

FILTRATE (contains MgO, K2 0. Na2 0, S0 3 . etc.) Atomic absorption analysis used to detect unprecipi- tated CaO.

Double precipitation of magnesium (as magnesium ammonium phosphate).

PRECIPITATE ignited and weighed as Mg-,P2 07 . Impurities such as CaO detected by XRF. Atomic ab- sorption used to determine amount of CaO in precipitate.

FILTRATE (contains K,0. IMa 2 0. S0 3 , etc.) Atomic absorption analysis used to detect unprecipitatcd CaO and MyO in the filtrate.

Figure 7. Flow sheet for the analyses of the "600 series" SRMs

.

11
Silica

SiC>2 was determined by classical double dehydration techniques given in the ASTM C114 method. After dissolution of the sample, silicic acid is dehydrated

by fuming with an appropriate acid. The solution is filtered and the silica is ignited, weighed, and then volatilized with hydrofluoric acid (HF) . The residue is ignited and weighed; the loss in weight represents silica. The results of these analyses are presented in Table 3. Because the substances remaining after "HF" treatment are re- introduced into the filtrate from the silica precipitate, and since silica is determined by "difference",

contaminants have little or no effect on the analysis. Nevertheless, two sets of silica precipitates were examined qualitatively by XRF techniques.

Aluminum, chromium, iron, and titanium were detected in some precipitates. No significant error is apparent resulting from these contaminants.

The presence of small amounts of fluoride (less than about 0.3 percent) or boron (less than 0.1 percent) will not cause significant errors by

volatilization during ignition of the silica precipitate prior to "HF" treatment. Since these SRMs contain 0.08 percent or less of fluoride and less than 0.01 percent boron, very little error is likely to result. Table 3. Results of the Analyses of Si02, % by wt. Gravimetric AAS SRM Average n Std Dev Average n Std Dev

633 21.88 7 0.023 21.88 5 0.062

634 20.73 8 0.024 20.79 5 0.091

635 18.41 9 0.030 18.37 5 0.065

636 23.22 10 0.024 23.29 5 0.078

637 23.07 9 0.046 23.09 5 0.078

638 21.48 7 0.035 21.51 5 0.049

639 21.61 7 0.034 21.63 5 0.116

An extensive analytical program to detect and quantitate silica remaining in the filtrate was undertaken using procedures based on the "molybdenum blue"

method. In every case, the optical absorbance of the sample "blank" solution

was at least three fourths of that of the sample indicating that the amount of silica unprecipitated is less than 0.02 percent. XRF analyses of the ammonium hydroxide ("R2O3") group precipitate, and of the calcium and magnesium precipitates, did not detect silica at a detection limit

of 0.04 percent.

Atomic absorption results, also shown in Table 3, are in good agreement with

the gravimetric data. "R2O3 " Group (Aluminum. Iron. Phosphorus. Titanium. Chromium and Zinc) The combined group, "R2O3", was determined by the classical double precipitation method given in ASTM C114 using ammonium hydroxide as precipitant- - followed by ignition to convert all elements to the oxide form.

12
The solutions from the silica determination, after combining with residue from

the "HF" volatilization step, were used for this analysis. The data are given

in Table 4. Table 4. Results of the Analyses of the "R2O3" Group, % by wt

.

SRM Average n Std Dev

633 634

635

636 637

638 639

8.47 8.54

9.40

4.92

5.55 8.42

7.09

3

34

44

3

3

0.076

0.053

0.043 0.071

0.062 0.053

0.023

Two sets of mixed oxide precipitates were analyzed by XRF spectroscopy. The group members aluminum, iron, titanium, zinc, and chromium, were detected in all the specimens. Zirconium was detected in six of the samples; calcium in

two, and nickel possibly in one. Phosphorus is known to be present in all the precipitates, but analysis for it was not carried out. Using standard addition techniques, reanalysis by XRF indicated that the quantities of nickel present were less than 0.01 percent. Using AAS procedures, and standards prepared to contain amounts of iron and aluminum

approximately equal to those in the sample, the amounts of calcium, magnesium,

potassium, and sodium oxides in the precipitates were found to be less than

0.01 percent. Because of questionable aluminum data for SRM 635 (to be discussed later) , the precipitate for this sample was also analyzed by optical emission

spectrographic methods. The only impurity of consequence was silicon. However, since the soluble silica data revealed no unusual amounts of silica in the solution from the silica removal step, this interference is small (0.02

percent or less). One set of filtrates from the "R2O3" group precipitate step was analyzed by AAS methods for aluminum and iron. These elements were not detected in the filtrate - indicating complete precipitation.

Fe203 was determined on separate samples by the volumetric titration method

given in ASTM C114 standard methods of analysis. These data are given in Table

5. The values reported are verified by the AAS data. It is noted that both

methods give similar results.

Iron Oxide

13
Table 5. Results of the Analyses of Fe203, % by wt

Volumetric AAS SRM Average n Std Dev Average n Std Dev

633 4.20 3 0.006 4.25 5 0.019

634 2.84 3 0.010 2.87 5 0.022

635 2.61 3 0.012 2.63 5 0.017

636 1.61 3 0.006 1.62 5 0.011

637 1.80 3 0.006 1.81 5 0.015

638 3.55 3 0.000 3.58 5 0.030

639 2.40 3 0.000 2.40 5 0.016

Titanla

T1O2 was determined on separate samples by a colorimetric method using Tiron

reagent, as developed by others and refined for cement by Jugovic . The data

are given in Table 6. The Tiron method is more sensitive than the classical

peroxide method given in ASTM C114. Table 6. Results of the Analyses

of Ti02, % by wt

SRM Average n Std Dev

633 0.238 3 0.003

634 0.293 3 0.004

635 0.319 3 0.006

636 0.178 3 0.006

637 0.210 3 0.005

638 0.252 3 0.004

639 0.316 3 0.003

Phosphorus Oxide

P2O5 was determined on separate samples by the "molybdenum blue" colorimetric

method given in the ASTM standard method. The data are given in Table 7. Table 7. Results of the Analyses of P2O5 > % by wt • SRM Average n Std Dev

633 0.238 3 0.002

634 0.095 3 0.001

635 0.169 3 0.001

636 0.084 3 0.001

637 0.244 3 0.001

638 0.062 3 0.001

639 0.082 3 0.001

14
Zinc Oxide

ZnO was determined on separate samples by AAS, using a standard addition

technique [4]. The values are given in Table 8. Table 8. Results of the Analyses of ZnO, % by wt

.

SRM Average n Std Dev

633 0.005 1 634 0.024 1 635 0.007 1 636 0.027 1 637 0.012 1 638 0.095 2 0.007

639 0.007 1

Chromium Oxide

Cr203 was determined on separate samples by AAS, using a standard addition

technique [4]. The data are given in Table 9. Table 9. Results of the Analyses of Cr203 , % by wt

.

SRM Average n Std Dev

633 0.008 2 0.001

634 0.076 2 0.001

635 0.005 2 0.000

636 0.006 2 0.001

637 0.010 2 0.001

638 0.010 2 0.000

639 0.005 2 0.000

Alumina

AI2O3 was determined by difference ("R2O3" percent minus "X2O3" percent),

subtracting the amounts of iron, titanium, phosphorus, zinc, and chromium

oxides from the ammonium hydroxide group total. The data are given in Table

10. Alumina was also determined by AAS and the values are in good agreement

(generally within 0.02 percent) except for SRM 635 which differs by 0.16 percent

.

15
Table 10. Results of the Analyses of AI2O3, % by wt

.

Determination by Difference AAS SRM 0R2Q.?>'1 £l2C>3 Std Dev Average n Std Dev

633 8 47 4 69 3 78 0 062 3 79 5 0 029 634 8 54 3 33 5 21 0 044 5 18 5 0 044

635 9 40 3 11 6 29 0 038 6 13 5 0 052

636 4 92 1 90 3 02 0 062 3 07 5 0 029

637 5 55 2 27 3 28 0 054 3 24 5 0 015

638 8 42 3 97 4 45 0 044 4 48 5 0 026

639 7 09 2 81 4 28 0 019 4 29 5 0 023

An extensive analytical program was carried out to determine a cause for this large difference. Several "R2O3" precipitates for this sample were analyzed by XRF spectroscopy in the hope of disclosing previously undetected components. None were detected. Similar analyses were made by optical emission

spectroscopy. In this case, other elements were detected- -boron , vanadium,

copper, lead, tin, nickel, molybdenum, and silver. However, the amount of each

of these elements present was much less than 0.01 percent.

The possibility of interference in either gravimetric or atomic absorption

methods by the large amounts of sulfate exists, but experiments designed to determine the effect of sulfate on the atomic absorption intensities for aluminum failed to disclose significant interference.

Manganese Oxide Mn203 was determined on separate samples by AAS . The data are given in Table

11. Experience indicates that the atomic absorption analysis for manganese in cement is much more precise and accurate than that given by the method in ASTM

C114. Prior to the calcium group determination, manganese was not removed by the usual bromine oxidation procedure because it was found that substantial amounts

of manganese (particularly in SRM 635) remained in solution until the calcium

precipitation step. When this manganese was detected in the calcium oxide

precipitate, a search was made for a more quantitative method for its removal. The coprecipitation (or zirconium collector) method of Peck [5] was found to be excellent, and was used for succeeding analyses. The method removes the manganese prior to the calcium determination step by coprecipitating it with

zirconium hydroxide.

Manganese separated by the method of Peck was determined by dissolution and quantitation by AAS using pure manganese standards. The results are also listed in Table 11. These data show that only a small amount of manganese is lost by the Peck procedure. Some is undoubtedly entrapped in the mixed oxide group ("R2O3") precipitate and some remains unprecipitated until the calcium or magnesium steps.

16
Table 11. Results of the Analyses of Mri203 , % by wt.

Separate Samples Recovered Samples

SRM Average n Std Dev Average n Std Dev

633 0 ,04 3 0 ,006 0,.03 2 0 ,000 634 0 ,28 3 0 ,006 0..26 2 0 ,028 635 0,.09 3 0 ,000 0..07 4 0 ,017 636 0,,12 3 0 ,006 0,,11 3 0 ,000 637 0,,06 3 0 ,000 0,,04 4 0 .006 638 0,,05 3 0 ,000 0,.04 4 0 .006 639 0.,08 3 0 .006 0,,07 4 0 ,000

Calcium Group

CaO (+ SrO) was determined by the classical double precipitation method

employing oxalate. Most of the strontium is also precipitated in this procedure, and the term "calcium group" is applied. The results are given in Table 12. Table 12. Results of the Analyses

of Calcium Group, % by wt

.

SRM Average n Std Dev

633 64.75 6 0.047

634 62.65 5 0.072

635 59.98 6 0.047

636 63.53 8 0.057

637 66.10 5 0.126

638 62.11 5 0.087

639 65.85 6 0.072

Analyses of the calcium group precipitate, after removal of manganese by the Peck method, were made by XRF spectroscopy. No manganese was found in the precipitates

.

The filtrate from the calcium group precipitation step was analyzed for calcium

by AAS . Calcium was detected, but because of the large amounts of ammonium

salts, quantitative analysis could not be easily made. However, since calcium

appeared in the magnesium precipitate, analysis of the latter was chosen as the more suitable method for determining the unprecipitated calcium. Strontium Oxide

SrO was determined on separate samples by the use of AAS. The date are given

in Table 13. There is no ASTM C114 method for the determination of strontium.

The ignited oxide precipitates of the calcium group were dissolved in acid and strontium determined by AAs using standards containing approximately equivalent

amounts of calcium and acid. The data, also given in Table 13, suggest that

17
the calcium group precipitation step is not quantitative for SrO. Table 13. Results of the Analyses of SrO, % by wt

.

Separate Samples CaO Precipitate

SRM Average n Std Dev Average n Std De 633 0.31 3 0.006 0.28 4 0.013

634 0.12 3 0.010 0.11 4 0.008

635 0.21 3 0.010 0.18 4 0.006

636 0.04 3 0.000 0.04 5 0.000

637 0.09 3 0.006 0.08 4 0.005

638 0.07 3 0.006 0.06 4 0.010

639 0.15 3 0.006 0.12 4 0.015

Magnesia

MgO was determined by the classical double precipitation method using ammonium

phosphate, with ignition to the pyrophosphate. The analytical data are given

in Table 14. It is noted that these values are useful for comparison with ASTM

C114 results. However, the inclusion of calcium in the precipitate (as noted

above) causes these data to be slightly erroneous.

The magnesium oxide precipitates were analyzed by XRF spectroscopy. Small amounts of calcium were detected in each. The precipitates were dissolved in acid and analyzed by AAS , using standard solutions containing approximately

equivalent amounts of magnesium and acid. The amounts of calcium determined

(0.02 to 0.04 percent) were used to correct both the calcium and magnesium

values

.

The percent of CaO in MgO in Table 15 must be multiplied by the appropriate

conversion factor (0.6674) before it is used for correcting the MgO value in Table 14. The reason for this is as follows: Calcium occurs in the Mg2P2<-) 7 precipitate as calcium phosphate, Ca3(P04)2- The weight of calcium oxide in the Mg2?207 (as determined by AAS) is multiplied by 1.8437. This value is subtracted from the weight of Mg2?207 before the percent MgO is calculated.

The factor 1.8437 is obtained by dividing the molecular weight of Ca3(P04)2 by

3 times the molecular weight of calcium oxide. The filtrate from the magnesium precipitation step was analyzed by AAS for calcium and magnesium. While neither was detected, the severe interference of large amounts of ammonium ion in the filtrate makes this determination

uncertain.

18
Table 14. Results of the Analyses of MgO, % by wt. Gravimetric CaO in AAS

SRM Average n Std Dev MgO Difference Average n Std Dev

633 1.06 4 0.026 0.02 1.04 1.07 5 0,,012 634 3.33 5 0.023 0.03 3.30 3.39 5 0.,022 635 1.26 3 0.053 0.03 1.23 1.28 5 0. Oil

636 3.98 6 0.035 0.03 3.95 3.99 5 0.,020 637 0.68 3 0.031 0.01 0.67 0.71 5 0 ,004 638 3.86 5 0.059 0.03 3.83 3.88 5 0 .030 639 1.28 5 0.030 0.02 1.26 1.30 5 0 ,007

AAS data are also given in Table 14 for comparison purposes. The results obtained are slightly higher than the corrected gravimetric results. The reason for this difference is not known for certain, but may be due to small positive errors in the MgO certified values of the "1000 series" SRMs which

were used to prepare the AAS calibration curves. Calcium Oxide

CaO was determined by "difference" (calcium group minus the strontium

determined in the group precipitates). To this net calcium oxide must be added

the amount that was unprecipitated. Fortunately, it is coprecipitated with

magnesium, and can be determined. This determination was discussed above under

the magnesium oxide determination. However, this correction is not made during

an ASTM C114 referee analysis, and thus for comparative purposes, "uncorrected"

data, as well as corrected data need to be reported. These data are given in Table 15 along with the calcium oxide values determined by AAS. These values

agree with the corrected CaO values. Table 15. Results of the Analyses of CaO, % by wt. SrO Uncor- CaO

+ rected in AAS SRM CaO SrO CaO MgO CaO Std Dev Average n Std Dev

633 64. 75 0.28 64.47 0.03 64. 50 0. 044 64..53 5 0..14 634 62. 65 0.11 62.54 0.04 62. 58 0. 065 62.,70 5 0,,14 635 59. 98 0.19 59.79 0.04 59. 83 0. 043 59 .77 5 0.,11 636 63. 53 0.04 63.49 0.05 63,,54 0. 050 63 .57 5 0.,16 637 66.,10 0.08 66.02 0.02 66,,04 0. 113 66 .05 4 0.,14 638 62,,11 0.06 62.05 0.04 62,,09 0. 078 62 .08 5 0.,12 639 65,,85 0.12 65.73 0.03 65,,76 0. 067 65 .70 5 0..10

Sulfur Trioxide

SO3 was determined on separate samples by ASTM C114 referee method (using a precipitation with barium chloride) and as total sulfur (using an induction

furnace to evolve sulfur oxides, which were determined by titration). These results are listed in Table 16.

19
Since silica and iron are reported to cause interference under certain

circumstances with the determination of SO3 , a procedure in which most of the silica and the ammonium hydroxide group elements were removed (either by

dehydration or by precipitation with ammonia) was used before precipitation of sulfur as barium sulfate. The agreement of results between the gravimetric and the total sulfur, except

for SRM 635, indicates that no significant sulfide sulfur exists in the SRMs

An ASTM C114 sulfide determination was made on SRM 635 and none was found. Table 16. Results of the Analyses of SO3 , % by wt

SRM Average n Std Dev Average n Std Dev

633 2..20 2 0 .000 2,,20 3 0 .046 634 2,,21 2 0 .028 2,.18 3 0 .012 635 7,.07 2 0 .028 7,.23 3 0 .115 636 2..31 2 0 .000 2..30 2 0 .042 637 2..38 2 0 .014 2 .40 2 0 .021 638 2,.34 2 0 .021 2 .37 2 0 .014 639 2..48 2 0 .021 2..46 2 0 .000

Potassium and Sodium Oxides These alkalies were determined on separate samples by AAS . The results are given in Tables 17 and 18. Atomic absorption was selected as a matter of convenience. This method and flame photometry, as designated in ASTM C114, should give comparable results. Table 17. Results of the Table 18. Results of the Analyses of K2O, % by wt . Analyses of Na20, % by wt

SRM Average n Std Dev SRM Average n Std Dev

633 0.17 5 0.000 633 0.64 5 0.010

634 0.42 5 0.007 634 0.15 5 0.005

635 0.45 5 0.004 635 0.07 5 0.005

636 0.59 5 0.009 636 0.11 5 0.004

637 0.25 5 0.005 637 0.15 5 0.004

638 0.59 5 0.005 638 0.13 5 0.004

639 0.06 5 0.000 639 0.65 5 0.004

Fluoride

Fluorine (as fluoride ion) was determined on separate samples by an ion- selective electrode procedure developed at PCA by W.F. Mivelaz [6], in which a calomel reference electrode, a specific ion meter, and two standard fluoride

solutions (0.01 and 0.10 percent fluorine) are used. In this procedure, the sample is dissolved in an acidified alum solution and the fluoride ion is freed by the addition of sodium citrate which complexes the aluminum. The results

are given in Table 19. 20

:
Table 19. Results of the Analyses

of Fluoride, % by wt. SRM Average n Std Dev

633 0.08 4 0.000

634 0.08 4 0.006

635 0.04 4 0.006

636 0.06 4 0.006

637 0.04 4 0.005

638 0.04 4 0.005

639 0.02 3 0.000

To determine if boron would interfere, known amounts of boric acid were introduced into some samples. No interference was observed. Miscellaneous Element Determinations of barium, boron, chloride, and zirconium were made on separate

samples. All were less than 0.01 percent.

Ignition Loss

Loss -on- ignition (1000 °C for 30 minutes) was determined on separate samples

using the ASTM C114 method. The data are given in Table 20. Table 20. Results of the Analyses

of Ignition Loss, % by wt

.

SRM Average n Std Dev

633 0.75 3 0.006

634 1.62 3 0.036

635 3.24 3 0.017

636 1.16 3 0.026

637 1.69 3 0.055

638 0.95 3 0.036

639 1.00 3 0.025

Summary

The results of all analyses are given in Table 21 along with the pooled

standard deviations for the seven cements. These pooled standard deviations

were determined as

2 _ 2(ni-l)s2

S P ~ S(ni-l)

where it was assumed that the precision was the same for all of the cements. These results formed the basis for the certification of SRMs 633 through 639.

21
Table 21. Final Results for the "600 Series" SRMs , % by wt

Component SRM S P 633 634 635 636 637 638 639

CaO 64 50 62 58 59 83 63 54 66 04 62 09 65 76 0 07 SiOoz 21 88 20 73 18 41 23 22 23 07 21 48 21 61 0 03 A1 2 0 3

3 78 5 21 6 29 3 02 3 28 4 45 4 28 0 06

Fe 2°3 4 20 2 84 2 61 1 61 1 80 3 55 2 40 0 01

so 3 2 20 2 21 7 07 2 31 2 38 2 34 2 48 0 02 MgO 1 04 3 30 1 23 3 95 0 67 3 83 1 26 0 04 K2 0 0 17 0 42 0 45 0 59 0 25 0 59 0 06 0 01 Ti02 0 24 0 29 0 32 0 18 0 21 0 25 0 32 0 01 Na2 0 0 64 0 15 0 07 0 11 0 15 0 13 0 65 0 01 SrO 0 31 0 12 0 21 0 04 0 09 0 07 0 15 0 01

P 2 0 5 0 24 0 10 0 17 0 08 0 24 0 06 0 08 <0 01 Mn2 03 0 04 0 28 0 09 0 12 0 06 0 05 0 08 0 01

F 0 08 0 08 0 04 0 06 0 04 0 04 0 02 0 01 ZnO 0 01 0 02 0 01 0 03 0 01 0 10 0 01 <0 01 Cr 2 0 3 0 01 0 08 0 01 0 01 0 01 0 01 0 01 <0 01 Ign Loss 0 75 1 62 3 24 1 16 1 69 0 95 1 00 0 04 Total 100 1 100 .0 100 0 100 0 100 0 100 0 100 2 Sp is the pooled standard deviation for the seven SRMs.

22
SRMs 1880 and 1881

It became apparent that for the portland cement SRMs to be more useful to the cement industry in calibrating instrumental methods, some new standards should

be certified with compositions that either filled in some blank areas in the composition ranges or extended them (see Figure 1). Accordingly, a questionnaire was distributed to members of ASTM Committee C-l on Cement that solicited suggestions for the chemical composition of two new SRMs. A copy of

the letter is reproduced in Appendix D. The majority of nearly 50 responses expressed the following desires:

1. SO3 content should be greater than 2.50%, preferably near

3.00% or 3.50%.

2. K2O content should be between 0.6% and 1.0%.

3. Na20 content should be between 0.2% and 0.6%.

4. MgO content should be approximately 2.5% or 5.0%.

5. Fe203 content should be approximately 3.25% or 5.0%.

6. AI2O3 content should be approximately 4.8% or 5.2%.

7. Si02 content should be approximately 20% or 22%.

8. CaO content should be approximately 63% or greater than 66%. A few respondents requested a low- iron, high-alumina cement, while a few other respondents wanted higher levels of trace elements (such as Cr, Zn, and Mn) than appeared in the "600 series" SRM. Several respondents suggested use of cements with which they were familiar, none of which appeared to satisfy the majority's requests. Therefore, it was decided to locate two or more cements

that either alone or blended together would meet the needs of the majority of surveyed respondents. After evaluating typical analyses from more than a dozen commercially available cements , approximately 200 kg of Type I portland cement was obtained from the

St. Marys Cement Company in St Marys, Ontario, and the Texas Cement Company in Buda, Texas to be issued as SRM 1880. XRF analyses of each cement indicated

that a 50:50 blend would produce a standard with levels of most elements very

close to the desired concentration (see Appendix F)

.

To eliminate segregation of the packaged SRM, the cements were ground and classified separately in a Vortec M-l impact mill and Vortec C-13 air classifier until all of the cement particles were between 0.5 and 45 /xm as measured by a Micromeritics Sedi Graph* particle size analyzer (see Appendix

F). Approximately 100 kg of each cement was weighed and transferred to a 19-ft. steel ribbon blender and mixed for 2-1/2 hours. One -third of the cement was transferred to a plastic - lined 55-gal steel drum; the next third was caught in

a plastic-lined 30-gal steel drum; and the final third was transferred to the same 55-gal drum. The cement in the smaller drum was then tested for

* In order to adequately describe materials and experimental procedures, it was occasionally necessary to identify commercial products by manufacturer's name

or label. In no instance does such identification imply endorsement by the National Bureau of Standards nor does it imply that the particular products or equipment is necessarily the best available for the purpose.

23
homogeneity by analyzing 18 grab samples for sulfur, iron, and loss-on- ignition

in accordance with ASTM C114 refer procedures (see Table 22) . To improve the homogeneity, the cement was returned to the blender and mixed for four additional hours and then transferred as before. Six grab samples from the 30- gal drum were analyzed for iron with the results indicated in Table 22. These results verified that the cement was well blended and ready for packaging. Table 22. Homogeneity of Blended Cements, SRM 1880, % by wt

.

2-1/2 Hours 6-1/2 Hours Blender SO3 Fe203 Ign. Loss Fe203

Top 3.6910.014 2.93±0.000 1.40±0.010 2.81±0.000 Middle 3.68±0.021 2.9110.028 1.3610.005 2.8210.021 Bottom 3.6810.000 2.9410.057 1.3810.017 2.8110.014

The approximate composition of the second cement standard was selected after considering the survey responses and the final composition of SRM 1880. In consultation with cement industry representatives, it was decided that SRM 1881 should have greater than 1% K2O, greater than 4.5% Fe203, and a SO3 level near

3.75%. After evaluating typical analyses from many commercially available

cements, it was decided that a research cement identified as LTS-41 came closest to the desired composition. This cement had been obtained in 1941 and stored in steel drums in PCA since that time. It was manufactured by the former Alpha Portland Cement Company in Birmingham, Alabama. By testing the cement for loss-on- ignition, it was concluded that the cement had not gained

significant moisture during storage.

To discourage segregation of the packaged SRM, the cement was ground and classified in a Vortec M-l impact mill and Vortec C-13 air classifier until the cement particles were less than 40 /zm (see Appendix F) . Approximately 72 kg of cement was processed in this manner. Because additional gypsum was needed to increase the SO3 content to the desired

level of 3.75%, several methods of blending (homogenizing) the cement with gypsum were studied, including paddle mixing and ball milling. A 0.14-m mortar mixer with rubber wiper blades was tried first with 91 kg of a test cement and

1.6 kg of gypsum. After mixing for 60 minutes there seemed to be a difference

between samples taken from the top and bottom of the mixer. These samples were tested for total sulfur using a Leco sulfur analyzer. A 0.07-m ceramic- lined

mill was tried next with equal charges (22 kg) of cement and gypsum and alumina balls (equal weights of 1-in, 3/4-in, and 1/2-in diameters). After milling for

60 minutes the blending was questionable. A 0.14-m steel-lined ball mill was tried next using the same ratio of balls to the cement charge. The results obtained in this test were more encouraging. Based on these results and discussions with members of the PCA staff, it was decided to use a ratio of 3 to 1 of high-density (90%) alumina balls to the cement and gypsum charge in the steel-lined mill. To simulate the particle size distribution of gypsum typically found in cements, the gypsum was first ground to high fineness in a small (0.03 m) steel ball mill with 34 kg steel balls graded from 1/2 in to 7/8 in. Approximately 4 kg gypsum was added and ground at 70 rpm for 7500 revolutions. The mill was

24
stopped every 1500 revolutions and the gypsum scraped from the inner mill wall. The gypsum was discharged through a grate by turning the mill an additional 200 revolutions . This finely ground gypsum contained 2 . 1% greater than 200 mesh

(70 /im) . The entire batch was brushed through a 200 mesh sieve yielding about

3 . 9 kg with a Blaine specific surface area of 10,725 cm^/g (density = 2.37

g/cm^, bed porosity = 0.50). The ground and classified cement was split into three batches of 24 kg each,

homogenized separately for 10 minutes and then discharged into separate

containers. Chemical analysis on composite grab samples indicated 1.67% SO3 in the cement. To achieve the desired level of SO3 , approximately 1.2 kg of Terra Alba gypsum was added to each batch. Each 24-kg batch of the cement was then blended separately in the steel-lined

ball mill with 66-kg alumina balls graded as previously described. The mill

was turned at 30 rpm for 15 minutes, stopped, the inner wall scraped, and the mill turned for an additional 15 minutes. The mill was then stopped, a discharge grate attached, and the mill turned for 5 minutes to discharge the cement. This blended cement was returned to its original container. Each of

the three batches was homogenized in this manner and cross -blends between the batches were made according to the scheme shown in Figure 8. Grab samples taken from different locations in the mill during blending indicated

satisfactory homogenization was achieved. After blending, 12 grab samples of about 10 g each were taken to check the homogeneity. Because the cement was in three 5 -gal cans, two samples were

taken from the upper and lower halves of each can. Briquets were pressed from

6 g of each sample for XRF analysis for calcium, sulfur, and iron. The results

of these preliminary homogeneity analyses are shown in Table 23. These results verified that the cement was well blended and ready for packaging. Table 23. Prepackaging Homogeneity of SRM 1881, % by wt

CaO SO3 Fe_2Q3 Can 1 2 3123123

Top 60.00 60.02 59.95 3.90 3.88 3.90 5.00 4.98 4.97

Bot. 60.03 59.88 60.19 3.90 3.92 3.94 5.00 4.99 5.00

SPvMs 1880 and 1881 were packaged in one -dram stoppered shell vials, flame sealed within slightly larger shell vials, using the same method as the previous cement standards. A small glass wool disc placed in the outer vial

protected the bottom of the inner vial during the flame sealing. See Appendix

E for complete descriptions of the packaging materials.

During the first phase of preparing these two SRMs , PCA investigated the possibility of packaging the cements in modern flexible materials. See Appendix G for details on this study.

25
BATCH #1 BATCH #2 BATCH #3

CROSSMATCH #1 CROSS-BATCH #2 CROSS-BATCH #3

Figure 8. Scheme for mixing and blending the cement for SRM 1881

26
An auger- type apparatus was used to fill each vial with cement. A 4 -gal

hopper was manually loaded with cement and the vials were then filled by

pressing a foot pedal to discharge the cement into one vial at a time. Approximately 20 vials per minute could be filled, each with 5 g of cement. The mass of cement going into each vial was checked with an electronic

analytical balance several times each day. The vial was then stoppered and placed upside-down into a larger outer vial. The glass-wool pad was pushed

down into the outer vial so that it rested against the bottom of the inner

vial. The vials were then placed on a conveyor to the flame sealing machine.

The sealing machine could seal about 18 vials per minute. The controls for flame size and temperature and vial rotation speed were all adjusted to produce

uniform, hemispherical glass seals. As the vials were conveyed away from the sealing machine, they were placed by

hand into cardboard trays. Usually, one operator performed this work for 30 minutes and then exchanged places with the person operating the filling

machine. Two additional people worked to cap and insert the vials. Three people could fill and seal about 3,000 vials per day. An entire lot of 10,000

vials was packaged in three and one -half days. The methods used in the chemical analysis of SRMs 1880 and 1881 were the same

as those used for the "600 series" SRMs, including the checking of precipitates

and filtrates for impurities. A 0.5-g sample was used in all cases. For the majority of the analyses, tests were performed on some of ten samples chosen by

stratified random selection such that each sample represented a single case of

the stored cement. Ten of the 12 cases were picked at random. The ten samples

permitted the chemists to perform analyses in sets of six (five unknowns and

one blank or standard sample)

.

Silica

Si02 was determined by the classical double dehydration technique. The results

of these determinations, as well as the confirming AAS results, are indicated

in Table 24. Table 24. Results of the Analys es of Si02, % by wt. Gravimetric AAS SRM Average n Std Dev Average n Std Dev

1880

1881 19.82 7 0.053

22.25 4 0.029

19.68 5 22.22 5 0.079

0.069

"R2O3 " Group (AI 2O3 . Fe o03. P2O5 • Ti02 - Cr o^2 - and ZnO) The combined group "R2O3" was determined by the classical double precipitation

method. See Tables 25 through 29 for the results.

27
Table 25. Results of the Analyses

of the "R2O3" Group, % by wt

SRM Average n Std Dev

1880 8.47 7 0.066

1881 9.19 4 0.026

Iron Oxide

Fe203 was determined on separate samples by the volumetric titration method and confirmed by AAS . See Table 26. Table 26. Results of the Analyses

of Fe203, % by wt

Volumetric AAS SRM Average n Std Dev Average n Std Dev

1880 2.91 3 0.006 2.88 5 0.010

1881 4.68 4 0.005 4.71 5 0.030

Titania

Ti02 in SRM 1880 was determined by a colorimetric method using Tiron reagent. In SRM 1881 it was also determined by XRF using standard additions. The ASTM

C114 colorimetric method (complexation with Tiron) produces slightly low values. This procedure requires a correction due to interference by iron in the sample. Extensive investigations of this method during the analysis of these SRMs revealed the precise amount of correction to be applied. It also revealed the existence of some unknown interference which produces low values

for Ti02 in cements . In checking the notes made during the original definitive

analyses of the "600 series" cements, it was found that all values obtained by

the Tiron method had been adjusted to agree with check samples from "1000 series" cements, which had been analyzed for Ti02 by the classical peroxide

me thod. To determine accurate values for Ti02 in these SRMs, analyses were performed by

the method of standard additions using both XRF and colorimetry. Samples were fused with NaOH for colorimetry or with I^B^Oy for XRF. Standard additions of Ti02 (using SRM 154b) were made in increments of 0.25% up to a total of 1.25% Ti02 for both methods. The net optical absorbances and net XRF intensities were plotted linearly against concentration. The concentrations of Ti02 in the samples were determined by extrapolation to zero measurement response. The results are given in Table 27. Additional tests of the "600 series" cements indicated that the present values are correct.

28
Table 27. Results of the Analyses

of TiC>2, % by wt. Colorimetric XRF

SRM Average n Std Dev

1880 0.230 10 0.003

1881 0.248 2 0.002 0.217

Phosphorus Oxide

P2O5 was determined on separate samples by the "molybdenum blue" colorimetric

method. See Table 28 for the results. Table 28. Results of the P2O5 , % by wt

SRM Average n Std Dev

1880 0.292 10 0.001

1881 0.091 4 0.001

Zinc Oxide

ZnO was determined on separate samples by AAS using a standard addition

technique. The value for each SRM was found to be 0.01 percent.

Chromium Oxide

Cr203 was determined on a separate sample by AAS. The value for each SRM was found to be less than 0.01 percent.

Alumina

AI2O3 was determined by difference (subtracting the amounts of Fe203 , Ti02

P2O5, and ZnO from the "R2O3" group amount) and confirmed by AAS. See Table 29 for the results. Table 29. Results of the Analyses of AI2O3

% by wt

Bv Difference AAS SRM AI2Q3 Std Dev Average n Std Dev

1880 8.47 3.44 5.03 0.064 5.05 4 0.037

1881 9.19 5.03 4.16 0.030 4.21 5 0.034

Manganese Oxide

Mn203 was determined on separate samples by AAS. See Table 30 for the results.

29
Table 30. Results of the Analyses

of Mn2C>3 , % by wt

SRM Average n Std Dev

1880 0.08 5 0.000

1881 0.26 5 0.000

Calcium Group

CaO + SrO was determined by the classical double precipitation method using

ammonium oxalate. See Table 31 for the results. Table 31. Results of Analyses

of the Calcium Group, % by wt

SRM Average n Std Dev

1880 63.09 6 0.064

1881 58.65 4 0.054

Strontium Oxide

The value of SrO for certification was determined on separate samples by AAS

The amount of SrO in the Calcium oxide precipitate was also determined by AAS. These values are given in Table 23. Table 32. Results of the Analyses

of SrO, % by wt

Separate Samples CaO Precipitate

SRM Average n Std Dev Average n Std Dev

1880 0.06 5 0.005 0.04 7 0.004

1881 0.11 5 0.000 0.09 3 0.002

Magnesia

MgO was determined by the classical double precipitation method. This value is corrected for the small amount of CaO in the precipitate as determined by AAS. This corrected value is confirmed by measurements on separate samples by AAS. See Table 33 for the results.

30
Table 33. Results of the Analyses of MgO, % by wt. Gravimetric CaO in AAS SRM Average n Std Dev MgO* Difference Average n Std Dev

1880 2.75 7 0.032 0.06 2.69 2.65 5 0.014

1881 2.70 4 0.009 0.07 2.63 2.65 5 0.008

r See correction factor on page 20. Calcium Oxide

CaO was determined by difference (subtracting the amount of strontium in the group precipitate and adding the amount of calcium in the magnesium

precipitate). See Table 34 for the results. Table 34. Results of the Analyses of CaO, % by wt. SrO SrO CaO

+ in in SRM CaO CaO MgO CaO Std Dev

1880 63.09 0.04 0.09 63.14 0.07 1881 58.65 0.09 0.11 58.67 0.06

Sulfur Oxide

SO3 was determined on separate samples using a precipitation with barium

chloride. The amount of SO3 in a composite sample of SRM 1881 was also determined by ion chromatography calibrated against standard sulfate solutions These results are indicated in Table 35. Table 35. Results of the Analyses of SO3 , % by wt. Gravimetry Chromatography

SRM Average n Std Dev

1880 3.37 5 0.013

1881 3.65 5 0.021 3.69

Potassium and Sodium Oxides These alkalies were determined on separate samples by AAS. See Tables 36 and

37 for the results.

31
Table 36. Results of the Table 37. Results of the Analyses of K2 0, % by wt. Analyses of Na2 0, % by wt. SRM Average n Std Dev SRM Average n Std Dev

1880 0.91 5 0.007 1880 0.28 5 0.000

1881 1.17 5 0.009 1881 0.04 5 0.000

Fluoride

Fluoride was determined on separate samples by a specific ion electrode

procedure. The results are indicated in Table 38. Table 38. Results of the Analyses

of Fluoride

,

% by wt

.

SRM Average n Std Dev

1880 0.104 10 0.0008

1881 0.094 5 0.0004

Chloride

Chloride was determined on separate samples by a potentiometric titration

procedure [6]. In this procedure the sample is decomposed in nitric acid,

filtered, and titrated potentiometrically with silver nitrate using a Ag/AgS

electrode. See Table 39 for the results. Table 39. Results of the Analysis

of Chloride, % by wt

.

SRM Average D Std Dev

1880 0.016 9 0.0015

1881 0.005 5 0.0005

Miscellaneous Elements

No significant amounts (less than 0.01 percent) of barium, boron, and zirconium

were found. Ignition Loss

Loss -on- ignition (1000 °C for 30 minutes) was determined on separate samples.

See Table 40.

32
Table 40. Results of Ignition

Loss , % by wt

.

SRM Average n Std Dev

1880 1.38 4 0.019

1881 2.01 5 0.018

The combined results of all these analyses are given in Table 41 along with the pooled standard deviations for the two cements. These results formed the basis

for the certification of SRMs 1880 and 1881. Table 41. Final Results for

SRMs 1880 and 1881, % by wt

.

SRM Constituent 1880 1881 <lp_

CaO 63 .14 58 .67 0..06 Si02 19 .82 22 .25 0 .05 A12 0 3 5 .03 4 .06 0 .06 Fe 2 0 3 2 .91 4 .68 0 .01 S03

3 .37 3 .65 0 .02 MgO 2 .69 2 .63 0 .03 K2 0 0 .91 1 .17 0 .01 Ti02 0 .23 0 .25 <0,.01 Na2 0 0 .28 0 .04 <0,.01 SrO 0 .06 0 .11 <0..01 P2 0 5 0 .29 0 .09 <0,,01 Mn2 0 3 0 .08 0 .26 <0 .01 F 0 .10 0 .09 <0..01 CI 0 .02 0 .01 <0.,01 ZnO 0 .01 0 .01 Cr2 0 3 <0 .01 <0 .01 Ign Loss l.:38 2 .01 0,,02 Total 100.2 100 .0

Sp is the pooled standard deviation for the two SRMs.

33
Conclus ion During the preparation of SRMs 1880 and 1881, several methods of blending

(homogenizing) the cements were studied. The effectiveness of a ribbon-type

blender, a paddle mixer, a rotating drum mixer, a ceramic pebble, and steel ball mills were tested. The paddle and drum mixers performed poorly, actually

causing a segregation in the samples. The pebble mill performed well with a ball -charge to sample weight ration of 3:1. However, extended time in the ball mill produced a sample of greater fineness. Thus, of the blenders tested, the ribbon blender worked best, yielding flowable powders; unfortunately, it is tedious to thoroughly clean because of the arrangement of the ribbon blades. A systematic study should be made to determine the effectiveness of twin- shell "V-blenders" with high-speed intensifier bars. The traditional flame sealed glass vials are excellent containers for portland

cement SRMs. Samples of cement which were sealed in glass vials and stored in

a 100%-relative-humidity room for two years showed no increase in loss-on- ignition or change in specific area. A sample of SRM 114, Portland Cement Fineness Standard, which had been sealed in glass vials for more than three decades is still being used. The filling and sealing of glass vials, however,

is a slow process. On the other hand, flexible packages offer the advantages

of light weight, a large surface for labelling, high-speed filling and sealing

with automated apparatus, and they will not break if dropped. The use of flexible packages, however, are doubtful. See Appendix G for a study of their performance under extreme conditions. While they can provide good barriers

against moisture and carbon dioxide, they are not intended for long-term

storage of materials, because the plastic films may deteriorate. Therefore,

developments in the flexible packaging industry should be monitored. When

plastic laminates become available with extended life, they should be carefully tested for their suitability as containers. It is noted that the Cement Association of Japan has begun to use flexible packages for their portland

cement fineness standards.

Since the completion of SRMs 1880 and 1881, a computer program was written by

R. Paule , P. Pella, and G. Y. Tao of NBS which performs a rigorous within and between analysis of variance. This program eliminates the use of "judgement"

when assessing the variability of homogenized samples. It is based on performing duplicate XRF analyses of samples fused with lithium tetraborate.

The program should be employed in evaluating the blending of cement SRMs in the future

.

Significant interferences found during the course of the analytical studies

are

:

(1) Approximately 0.1% CaO is found in the MgO precipitate. This correction

should be made for accurate MgO determinations.

(2) The gravimetric procedure for CaO has been replaced in ASTM C114-83a with a titration procedure. Because the gravimetric procedure is subject to interferences from strontium and magnesium, future analyses for certification of calcium in cements should be based on the titration and other instrumental methods.

34
(3) The gravimetric aluminum determination is also subject to interferences,

notably through the presence of phosphorus, titanium, and iron. If present

in sufficient quantities, chromium, zinc, and copper also interfere. Thus, future analyses for aluminum in cements should be based on instrumental methods

(4) The colorimetric method for titanium (using Tiron reagent) described in ASTM C114 and studied during the characterization of SRM 1881 gives values

that are consistently several hundredths of a percent low. The influence

of iron on the determination was investigated and its influence is now

known. It does not, however, account for the remaining consistently low values. Further work is needed on this method.

The analytical program has demonstrated that several interferences exist that must be taken into account to obtain the most accurate values when performing

gravimetric determinations.* On the other hand, instrumental analysis has reached a high level of reliability, precision and accuracy so that many

analyses previously performed by classical methods can be replaced by

techniques such as atomic absorption/emission, x-ray fluorescence, neutron

activation, mass spectroscopy, and plasma emission. Perhaps the most significant difficulty in performing classical gravimetric

analyses is simply that fewer and fewer chemists practice these methods and the precision and accuracy of these techniques depend on the skill of the analyst.

It is a tribute to the analysts who participated in this program, notably

Robert F, Crow of the PCA laboratories, that the gravimetric results are in excellent agreement with those of the instrumental techniques.

35
Acknowledgements

The preparation, packaging, and characterization of these portland cement SRMs was accomplished through the close cooperation of many people and organizations. Special credits are given to those listed below. NBS Staff Leonard Bean

Bruce E. Foster Harry H. Ku

Robert E. Michaelis

Stanley D. Rasberry

PCA Staff Robert F. Crow

N. R. Greening

Ernst LaBonde Joseph Leonard

Hugh Love Mick McCann William F. Mivelaz

Robert Monger

Celestino Palmiano

Heinz Seiler Charles Wilk

William G. Hine of Erlin, Hine Associates ASTM Committee C-l on Cement

The many cement manufacturers who contributed the cements from which the SRMs were made and for extensive laboratory time in performing analyses.

36
References

[1] ASTM C114-69, Standard Methods for Chemical Analysis of Hydraulic Cement,

American Society for Testing and Materials, Annual Book of ASTM Standards, Part 9.

[2] Jugovic, Z. T. , Application of Spectrophotometric and EDTA Methods for Rapid Analysis of Cement and Raw Materials, in Analytical Techniques for Hydraulic Cement and Concrete, ASTM Standard Technical Publication, STP No. 395, 1966, pp. 65-93.

[3] Crow, R. F. and Connolly, J. D., Atomic Absorption Analyses of Portland

Cement and Raw Mix Using a Lithium Metaborate Fusion, Journal of Testing

and Evaluation (ASTM), Vol. 1 (No. 5), September 1973, pp. 382-393.

[4] Crow, R. F. and Connolly, J. D., Analysis of Portland Cement, Prog. Analyt

.

Atom. Spectrosc, Vol. 1, 1979, p. 349.

[5] Peck, L. C, Systematic Analysis of Silicate, U. S. Geological Survey

Bulletin 1170, 1964.

[6] Mivelaz, W. F. et al .

, Test Methods of the PCA Analytical Chemistry

Laboratories, Portland Cement Association, February 1980, Sec. 4, pp. 1-20. Copies of the reports

(1) Cooperative Analyses of the "600 series" SRMs

.

(2) Definitive Analysis of the "600 series" SRMs.

(3) Preparation and Analysis of SRM 1880.

(4) Preparation and Analysis of SRM 1881. can be obtained from the Office of Standard Reference Materials, National Bureau of Standards.

37
Appendix A Copies of the certificates

SRM 177 1011

1013 1014

1015 1016

633 634

635

636

637

638 639 1880

1881
United states department of commerce

washington 25, d. c. J^attonal bureau of ^tanbarb*

Certificate of !3nalp£e£

Standard Sample 177

Portland Cement

i2

345—

6-„._

7

Average.

Si02

21.91 21.88 21.96

21.90

21.96

'21.91 21.93

21. 85 '21.97 21.90

21.93 21.94

21.87

A1,08

S.26

5.28 5.20

•5. 38

«5. 50 '5.26

5. 25 5.26

5. 24

'•• 5. 76

5. 36

5.31 5.30

FejO,

<*2. 43 2.40

>2. 39

2. 38 2.40

2. 38 '2.37

2. 39

2. 39

2. 36 '2.45

2. 36

2. 38 2.37

TiOi

0. 26

.28 .28

.25

p2o4

0.05

k.05 *.04

-.04

*.05 -.05

.05

.03

.04

.05

CaO

64.29

64. 28 64.41 64.27

64.37

'64. 26 64.37 64.40 '64.56

'64.35 64.27

64.18

64.38

SrO

0.05

'.05

MgO

2.43 2.42 2.46

2.45 2.48

'2.51 2.50

2.37

2.48 '2.48 2.40

2.48 2.44

so8

1.59

1.59

1.56

1.63 1.56

'1.55 1.60

1.55

1.62 '1.60

1. 58

1.61 1.60

Mn,0,

«0.05

.05 .04

«.04 .04

«.05 .06

.03 «.04 .06

.04 .04

.06

NaaO

'0.15

«. 15

'.14

'. 14

p. 15

p. 13

". 12 '.12

p. 13

'.13 '.12 ".12

'.16

,"•11

p. 13

K20

'0.57

«. 55

'. 57

'.57

". 59

". 56

".56

'.60 ".56

'. 58

'.51 ".55 ".57

".58

•Loss on

Ignition

1.11

1.11 1.15 1.19

1.19

1.04

1.17 1.17

1.16

1. 14 1.18

1.14

1.15

21.92 5.27 0.26 0.04 64.32 0.05 2.45 1.59 0.05 0.14 0.57

• HjOt-photometric method (ASTM Spec CI14-S6T).

* All values for CaO include SrO.

• 1 I heated at 900° to 1,000* C for 15 min. in a coreret latinum crucible (ASTM Spec. CI 14-5 3). * NH«CNS-photometric

• Molybdenum-blue photometric

' Flame photometric See AasL Chem. 27, 913 (1955).

* Period*te photometric

k Flame photometric by HF-HCIO4

• Gravimetric Decomposition with NHjCl-OCOu (ASTM Spec C114-53.)

i Indudej 0.12 FeO converted to FcfCkk Phosphovanadomolybdate method.

Federal Teat Methods. Standard No. 158 (1957). » NrW Ha digestion. ASTM alternate method (0 14-53).

• Gravimetric weighed at MgiPiOr.

• Omitted from average, value include* TiOj or PrOi. » Flame photometric (ASTM Spec C114-56T).

« Doable dehydration with HClOi with intervening

fihratfon.

• Not included in the average. Analvat 1 reported 0.004-perctnt LoO.

List <

1. Keith M. Sappenfield and R. A. Paulson, Analytical Chemistry Section, National Bureau of Standards.

2. Joseph R. Spann and J. J. Diamond, Concreting

Materials Section, National Bureau of Standards.

3. Harold Allen, Nonbituminous Section, Bureau of Public Roads, Washington, D. C.

4. F. S. Reagel and O. E. Brown, Marquette Cement

Manufacturing Co., Chicago, 111. 5. W. J. Limbach, Southwestern Portland Cement Co.,

< Fairborn, Ohio.

( Walter H. Price, Division of Engineering Laboratories, Bureau of Reclamation, Denver, Colo. Washington, D. C, November 25, 1957.

Analysts

7. F. P. Diener and O. A. Ellingson, Universal Atlas Cement Co., New York, N. Y.

8. L. R. Indermuehle, Southwestern Portland Cement

Co., Victorville, Calif.

9. K. E. Palmer, Ideal Cement Co., Fort Collins, Colo.

10. L. R. Pritchard, Lone Star Cement Corporation, New

York, N. Y.

11. W. C. Hanna and Leon Loomis, California Portland Cement Co., Colton, Calif. 12. W. J. McCoy and O. L. Eshenour, Lehigh Portland Cement Co., Research Laboratory, Coplay, Pa.

13. J. H. Walker, Portland Cement Association, Chicago,

111. 3 9 A. V. Astin, Director.
U. S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS WASHINGTON, D. C. 20234 PROVISIONAL CERTIFICATE OF ANALYSIS STANDARD SAMPLE 1011 PORTLAND CEMENT

Percent Si0

2 21.

3 A1

2 0

3 5.38 Fe

2 0

3 2.07 Ti0

2

- - 0.25

P2°5 33 CaO (+SrO) - 66.

Q SrO 0.11 MgO 1.12 S0

3 1.75 Mn

20

3

- 0.03 Na

20 .08 K

2 0 .26 Li

2 0 - (.002) Rb

2 0 (.001) Loss on Ignition 1.13 Values in parentheses are not certified but are given as added information,

A. A. Bates, Chief

Building Research Division

Washington, D. C. Revised Certificate, April 24, 1964 Original Certificate January 17, 1962 USCOWM-NBS-DC

40
U. S. Department of Commerce

Maurice.H. Sta.-.s Secretary

(Certificate of JVnal^sts

STANDARD REFERENCE MATERIAL 1013

Portland Cement

Percent

Si0 2 24.1 7 A1 2 03 3.30 Fe2 03 3.07 Ti0 2 0.20 P2 05 20

Rb^^^JJ.

Lo^^o)} Ig^tKiH

Values in parentheses are not certified but are given as added information.

Washington, D. C. 20234 A. A. Bates, Chief January 17, 1962 Building Research Division (Revised April 24, 1964)

(Reprinted March 16, 1970)

41
U. S. Department of Commerce

Maurice H. Stana

Secretary

National Bareau of Standards

. M. Bransoomb, Director

(Eerttfttate of ^nalgsts

Standard Reference Material 1014

Portland Cement

Si0

2

.

.

A1

2 03

. Fe2 03 Ti02

. p2 o5 •

Percent

. 19.^

. 6.38

. 2.50

. 0.25

. .32 CaO (+SrO) 63.3

Values in parentheses are not certified but are given as added information.

Washington, D. C. 20234

January 17, 1962

(Revised April 24, 1964) (Reprinted June 18, 1971)

A. A. Bates, Chief

Building Research Division

42
U. S. DEAPRTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS WASHINGTON, D.C. 20234

PROVISIONAL CERTIFICATE OF ANALYSIS

STANDARD SAMPLE 1015 PORTLAND CEMENT

Percent

Si0

2

- 20.

6

5 A1

2 0

3 — 5.04

Fe2°3

3 ' 27 Ti0

2 — 0.26

P2°5 " -°5 CaO (+ SrO) —- - 61. 4_

o SrO --- 0.11 MgO — 4.25

S0

3 2.28 Mn

20

3

- 0.06 Na

2 0 .16 K

2 0 --- .87 Li

2 0 (.004) Rb

2 0 —- - (.005) Loss on Ignition 1.70 Values in parentheses are not certified but are given as added information,

A. A. Bates, Chief

Building Research Division

Washington, D. C. Revised Certificate, April 24, 1964 Original Certificate January 17, 1962 USCOMM-NBS-DC

43
U. 8. Departj^^of^Commerce

.-tlonal purmfctm Standard!

Irector Certificate of glnalpjsijsf

STANDARD SAMPLE 1016

PORTLAND CEMENT

Percent

Si02 — 21. 0

5 AI2O3— ~ 4.97

Fe 203 3.71

Ti02

• —— 0.34

p2°5 " -13

CaO (+SrO)

SrO - MgO <\"fT~~^"^~ * 42

S03 ......--^\^"--

Na^R 4"--^-" .55

#0 4

ri 2o (.012)

Rb20 * (N.D.

Loss on Ignition 1.20

Values in parentheses are not certified but are given as added

information.

*N.D. = not' detected, but less than 0.001%

A. A. Bates, Chief

Building Research Division

Washington, D. C. Revised Certificate April 24, 1964

Original Certificate January 17, 1962

Certificate Reprinted January 17, 1969

USCOMM-NBS-DC 44
U.S. Department bf Commerce

MaJcclnEfialdrige

NaiionaJ ^Bureau of Standards

Ernest Ambler, Director National bureau nf ^taniaria

Certificate of Analgia

Standard Reference Material 633

Portland Cement

(Cap Color is Red)

This Standard Reference Material (SRM) is intended for use in checking chemical methods of analysis and in calibration of instrumental methods of analysis. The value listed for a constituent is the present best estimate of the "true" value based on the results of a definitive analysis program carried out in the laboratories of the Portland Cement Association by N. R. Greening, W. F. Mivelaz and R. F. Crow, with W. G. Hime of Erlin, Hime Associates acting as consultant. The certified value for a constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported;

for a subscript figure, the deviation is not expected to be more than ± 5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures. Constituent Percent by Weight Constituent Percent by Weight CaO*

Si0

2

64.50 21.88 Na^

SrO

0.64

.31 A1

203 3.78 p2o5 .24 Fe203 4.20 Mn203 .04 S03

| MgOa 2.2o

I.O4 FZnO

.08

.01 I^O

TiQ2

0.17

.24 Cr203 Ign. loss Totalb

.01 *3

100.06

"If the procedures of ASTM CI 14 are followed a small amount of CaO will remain in the MgO precipitate. In this case the uncorrected values given below for CaO and MgO should be used. CaO 64.4

7 MgO 1 .0

6

bA correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross total, was determined by

multiplying the percent fluoride by the ratio of the atomic weight of oxygen to the molecular weight of fluorine (0.421). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by B. E. Foster, R. E. Michaelis, and

C. L. Stanley. Washington, D.C. 20234 December 15, 1983 Stanley D. Rasberry, Chief

(Revision of certificates Office of Standard Reference Materials dated 2-24-77 and 6-12-74)

(Over) 45
HOMOGENEITY TESTING: Measurements were made at NBS on the portland cement supplied by the Lone Star Cement Corporation by S. D. Rasberry, M. M. Darr, and J. McKay by x-ray fluorescence analysis. The cement was

sampled at 16 locations and two briquettes were prepared for each one. Calcium and sulfur, chosen as key elements

for checking inhomogeneity, were determined by making four independent measurements on each briquette. A trend- elimination statistical design was employed in measuring the specimens. An analysis of these data indicated the homogeneity was satisfactory. Following these measurements the cement was thoroughly blended and packaged in hermetically sealed glass vials by personnel of the Cement and Concrete Research Laboratory and the Office of Standard Reference Materials. DEFINITIVE ANALYSIS PROGRAM OF THE PORTLAND CEMENT CORPORATION: "Wet" chemical

gravimetric methods were used for the major constituents CaO, Si0

2 , A1203 and MgO. (The methods were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe

203 was determined by dichromate titration and S03 by precipitation in an acid solution after removal of the ammonium hydroxide group and silica. Atomic absorption spectroscopy tech- niques were used for K^O, Na20, SrO, Mn203

, ZnO and Cr203

. Colorimetric techniques were used to determine Ti02 and P205 while fluoride was determined by an ion selective electrode method. Loss on ignition was determined at 1000°C. In each determination duplicate measurements were made on two to ten randomly selected samples. Through

the use of various techniques (colorimetric, gravimetric, potentiometric, optical emission elements were determined to be less than 0.01 wt%: CI, Ba, Zr, B, V, Ni, Mo, Sn, Pb, Cu, and Ag. The total of 100.06% of the certified constituents in the cement corroborates the evaluation and indicates that significant biases have not been introduced. CAUTION: To obtain the most accurate results by x-ray fluorescent methods of analysis, the user should compare his samples to the particular SRM that is most nearly the same in overall chemical composition. Alternatively, inter- element effect calibration procedures may be adopted to minimize biases.

46
U.S. Department of Commerce

Malcolm Baldrige

Secretary

National Bureau o| Standards

Ernest Amt>ter, Director National Bureau of Btatiiariifi

(Hzttifxtutt uf Analprta

Standard Reference Material 634

Portland Cement

(Cap Color is Gold)

This Standard Reference Material (SRM) is intended for use in checking chemical methods of analysis and in calibration of instrumental methods of analysis. The value listed for a constituent is the present best estimate of the "true" value based on the results of a definitive analysis program carried out in the laboratories of the Portland Cement Association by N. R. Greening, W. F. Mivelaz and R. F. Crow, with W. G. Hime of Erlin, Hime Associates acting as consultant. The certified value for a

constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported;

for a subscript figure, the deviation is not expected to be more than ±5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures.

Constituent Percent by Weight Constituent Percent by Weight

CaO3 62.5

g Na20 0.15 Si02 20.7

3 SrO .12 A1

203 5.2, p2o5 .10 Fe

203 2.84 Mn203 .28 S03 2.2, F .08 MgOa 3.30 ZnO .02 K20 0.42 Cr203 .08 TiQ2 .29 Ign. loss 1.6

2 Totalb 100.00

"If the procedures of ASTM CI 14 are followed a small amount of CaO will remain in the MgO precipitate. In this case the uncorrected values given below for CaO and MgO should be used. CaO 62.54 MgO 3.3

3 bA correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross total, was determined by

multiplying the percent fluoride by the ratio of the atomic weight of oxygen to the molecular weight of fluorine (0.421). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by B. E. Foster, R. E. Michaelis, and

C. L. Stanley. Washington, D.C. 20234 December 15, 1983 Stanley D. Rasberry, Chief

(Revision of certificates Office of Standard Reference Materials dated 2-24-77 and 6-12-74)

(Over) 47
HOMOGENEITY TESTING: Measurements were made at NBS on the portland cement supplied by the Universal Atlas Cement Division of United States Steel Corporation by S. D. Rasberry, M. M. Darr, and J. McKay by x-ray fluorescence analysis. The cement was sampled at 16 locations and two briquettes were prepared for each one. Calcium and sulfur, chosen as key elements for checking inhomogeneity, were determined by making four indepen- dent measurements on each briquette. A trend-elimination statistical design was employed in measuring the specimens. An analysis of these data indicated the homogeneity was satisfactory. Following these measurements the cement was thoroughly blended and packaged in hermetically sealed glass vials by personnel of the Cement and Concrete Research Laboratory and the Office of Standard Reference Materials. DEFINITIVE ANALYSIS PROGRAM OF THE PORTLAND CEMENT CORPORATION: "Wet" chemical

gravimetric methods were used for the major constituents CaO, Si0

2 , A1203 and MgO. (The methods were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe

203 was determined by dichromate titration and S03 by precipitation in an acid solution after removal of the ammonium hydroxide group and silica. Atomic absorption spectroscopy tech- niques were used for K20, NazO, SrO, Mn203

, ZnO and Cr203

. Colorimetric techniques were used to determine Ti02 and P205 while fluoride was determined by an ion selective electrode method. Loss on ignition was determined at 1000°C. In each determination duplicate measurements were made on two to ten randomly selected samples. Through

the use of various techniques (colorimetric, gravimetric, potentiometric, optical emission elements were determined to be less than 0.01 wt«7o: CI, Ba, Zr, B, V, Ni, Mo, Sn, Pb, Cu, and Ag. The total of 100.00% of the certified constituents in the cement corroborates the evaluation and indicates that significant biases have not been introduced. CAUTION: To obtain the most accurate results by x-ray fluorescent methods of analysis, the user should compare his samples to the particular SRM that is most nearly the same in overall chemical composition. Alternatively, inter- element effect calibration procedures may be adopted to minimize biases.

48
U.S. Department of Commerce

MaieolHEaaldrige National Bureau of ^taninariiH

Certificate of Anal^HtB

Standard Reference Material 635

Portland Cement

(Cap Color is Blue)

This Standard Reference Material (SRM) is intended for use in checking chemical methods of analysis and in calibration of instrumental methods of analysis. The value listed for a constituent is the present best estimate of the "true" value based on the results of a definitive analysis program carried out in the laboratories of the Portland Cement Association by N. R. Greening, W. F. Mivelaz and R. F. Crow, with W. G. Hime of Erlin, Hime Associates acting as consultant. The certified value for a

constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported;

for a subscript figure, the deviation is not expected to be more than ± 5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures.

Constituent Percent by Weight Constituent Percent by Weight CaOa 59.83 Na^ 0.07 Si02 18.4, SrO .21 A1

203 6.29 p2o5 .17 Fe

203 2.61 Mn203 .09 S03 7.07 F .04 MgOa 1.2

3 ZnO .01 up 0.45 Cr203 .01 TiQ2 .32 Ign. loss 3.24 Totalb 100.03

'If the procedures of ASTM CI 14 are followed a small amount of CaO will remain in the MgO precipitate. In this case the uncorrected values given below for CaO and MgO should be used. CaO MgO

59.7,

1.2,

bA correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross total, was determined by

multiplying the percent fluoride by the ratio of the atomic weight of oxygen to the molecular weight of fluorine (0.421). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by B. E. Foster, R. E. Michaelis, and

C. L. Stanley. Washington, D.C. 20234 December 15, 1983

(Revision of certificates dated 2-24-77 and 6-12-74)

Stanley D. Rasberry, Chief

Office of Standard Reference Materials

(Over)

49
HOMOGENEITY TESTING: Measurements were made at NBS on the portland cement supplied by the Penn-Dixie Cement Corp. by S. D. Rasberry, M. M. Darr, and J. McKay by x-ray fluorescence analysis. The cement was sampled

at 16 locations and two briquettes were prepared for each one. Calcium and sulfur, chosen as key elements for checking inhomogeneity, were determined by making four independent measurements on each briquette. A trend- elimination statistical design was employed in measuring the specimens. An analysis of these data indicated the homogeneity was satisfactory. Following these measurements the cement was thoroughly blended and packaged in hermetically sealed glass vials by personnel of the Cement and Concrete Research Laboratory and the Office of Standard Reference Materials. DEFINITIVE ANALYSIS PROGRAM OF THE PORTLAND CEMENT CORPORATION: "Wet" chemical

gravimetric methods were used for the major constituents CaO, Si0

2 , A1203 and MgO. (The methods were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe

203 was determined by dichromate titration and S03 by precipitation in an acid solution after removal of the ammonium hydroxide group and silica. Atomic absorption spectroscopy tech- niques were used for K20, Na20, SrO, Mn203

, ZnO and Cr203

. Colorimetric techniques were used to determine Ti02 and P2Os while fluoride was determined by an ion selective electrode method. Loss on ignition was determined at 1000°C. In each determination duplicate measurements were made on two to ten randomly selected samples. Through

the use of various techniques (colorimetric, gravimetric, potentiometric, optical emission elements were determined to be less than 0.01 wt<%: CI, Ba, Zr, B, V, Ni, Mo, Sn, Pb, Cu, and Ag. The total of lOO.O.Wo of the certified constituents in the cement corroborates the evaluation and indicates that significant biases have not been introduced. CAUTION: To obtain the most accurate results by x-ray fluorescent methods of analysis, the user should compare his samples to the particular SRM that is most nearly the same in overall chemical composition. Alternatively, inter- element effect calibration procedures may be adopted to minimize biases.

50
U.S. Department of Commerce

MalcQlnsLfiaMrige

Secretary

National Bureau of Standards

Ernest Ambler, Director National Mwczuu xrf #tani.ar&fi

(Hzttxfimtz of Analgia

Standard Reference Material 636

Portland Cement

(Cap Color is Yellow)

This Standard Reference Material (SRM) is intended for use in checking chemical methods of analysis and in calibration of instrumental methods of analysis. The value listed for a constituent is the present best estimate of the "true" value based on the results of a definitive analysis program carried out in the laboratories of the Portland Cement Association by N. R. Greening, W. F. Mivelaz and R. F. Crow, with W. G. Hime of Erlin, Hime Associates acting as consultant. The certified value for a

constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported;

for a subscript figure, the deviation is not expected to be more than ±5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures.

Constituent Percent by Weight Constituent Percent by Weight

CaO3 63.54 Na20 0.11 Si0

2 23.2 SrO .04 A1203 3.02 p2o5 .08 Fe203 1.61 Mn203 .12 S03 2.3, F .06 MgOa 3.9

5 ZnO .03 K20 0.59 Cr203 .01 TiQ2 .18 Ign. loss Totalb 100.00

a If the procedures of ASTM CI 14 are followed a small amount of CaO will remain in the MgO precipitate. In this case the uncorrected values given below for CaO and MgO should be used. CaO 63.4, MgO 3.9

8

bA correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross total, was determined by

multiplying the percent fluoride by the ratio of the atomic weight of oxygen to the molecular weight of fluorine (0.421). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by B. E. Foster, R. E. Michaelis, and

C. L. Stanley. Washington, D.C. 20234 December 15, 1983 Stanley D. Rasberry, Chief

(Revision of certificates Office of Standard Reference Materials dated 2-24-77 and 6-12-74) (Over)

51
HOMOGENEITY TESTING: Measurements were made at NBS on the portland cement supplied by the Arizona

Portland Cement Co. by S. D. Rasberry, M. M. Darr, and J. McKay by x-ray fluorescence analysis. The cement was

sampled at 16 locations and two briquettes were prepared for each one. Calcium and sulfur, chosen as key elements

for checking inhomogeneity, were determined by making four independent measurements on each briquette. A trend- elimination statistical design was employed in measuring the specimens. An analysis of these data indicated the homogeneity was satisfactory. Following these measurements the cement was thoroughly blended and packaged in hermetically sealed glass vials by personnel of the Cement and Concrete Research Laboratory and the Office of Standard Reference Materials. DEFINITIVE ANALYSIS PROGRAM OF THE PORTLAND CEMENT CORPORATION: "Wet" chemical

gravimetric methods were used for the major constituents CaO, Si0

2 , A1203 and MgO. (The methods were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe

203 was determined by dichromate titration and S03 by precipitation in an acid solution after removal of the ammonium hydroxide group and silica. Atomic absorption spectroscopy tech- niques were used for KjO, Na20, SrO, Mn203

, ZnO and Cr203

. Colorimetric techniques were used to determine Ti02 and P2Os while fluoride was determined by an ion selective electrode method. Loss on ignition was determined at 1000°C. In each determination duplicate measurements were made on two to ten randomly selected samples. Through

the use of various techniques (colorimetric, gravimetric, potentiometric, optical emission elements were determined to be less than 0.01 wt%: CI, Ba, Zr, B, V, Ni, Mo, Sn, Pb, Cu, and Ag. The total of 100.00% of the certified constituents in the cement corroborates the evaluation and indicates that significant biases have not been introduced. CAUTION: To obtain the most accurate results by x-ray fluorescent methods of analysis, the user should compare his samples to the particular SRM that is most nearly the same in overall chemical composition. Alternatively, inter- element effect calibration procedures may be adopted to minimize biases.

52
U.S. Department<>f Commerce

Malcolnrfinldjige

National tiurcan of Standards

Ernest Ambler, Director £fatt0tral l&mznu of ^taniaris

Certificate of Analgia

Standard Reference Material 637

Portland Cement

(Cap Color is Pink)

This Standard Reference Material (SRM) is intended for use in checking chemical methods of analysis and in calibration of instrumental methods of analysis. The value listed for a constituent is the present best estimate of the "true" value based on the results of a definitive analysis program carried out in the laboratories of the Portland Cement Association by N. R. Greening, W. F. Mivelaz and R. F. Crow, with W. G. Hime of Erlin, Hime Associates acting as consultant. The certified value for a

constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported;

for a subscript figure, the deviation is not expected to be more than ± 5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures.

Constituent Percent by Weight Constituent Percent by Weight CaOa 66.04 Nap 0.15 Si02 23.

7 SrO .09 A1203 3.2

8 p2o5 .24 Fe203 1.80 Mn203 .06 S03 2.3

g F .04 MgOa 0.67 ZnO .01 K20 .25 Cr203 .01 TiQ2

.21 Ign. loss 1.69 Totalb 99.97

a If the procedures of ASTM CI 14 are followed a small amount of CaO will remain in the MgO precipitate. In this case the uncorrected values given below for CaO and MgO should be used. CaO 66.0

2 MgO 0.6

g 'A correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross total, was determined by

multiplying the percent fluoride by the ratio of the atomic weight of oxygen to the molecular weight of fluorine (0.421). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by B. E. Foster, R. E. Michaelis, and

C. L. Stanley. Washington, D.C. 20234 December 15, 1983 Stanley D. Rasberry, Chief

(Revision of certificates Office of Standard Reference Materials dated 2-24-77 and 6-12-74)

(Over) 53
HOMOGENEITY TESTING: Measurements were made at NBS on the portland cement supplied by the Kaiser Ce- ment & Gypsum Corp. by S. D. Rasberry, M. M. Darr, and J. McKay by x-ray fluorescence analysis. The cement was

sampled at 16 locations and two briquettes were prepared for each one. Calcium and sulfur, chosen as key elements

for checking inhomogeneity, were determined by making four independent measurements on each briquette. A trend- elimination statistical design was employed in measuring the specimens. An analysis of these data indicated the homogeneity was satisfactory. Following these measurements the cement was thoroughly blended and packaged in hermetically sealed glass vials by personnel of the Cement and Concrete Research Laboratory and the Office of Standard Reference Materials. DEFINITIVE ANALYSIS PROGRAM OF THE PORTLAND CEMENT CORPORATION: "Wet" chemical

gravimetric methods were used for the major constituents CaO, Si02, A1203 and MgO. (The methods were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe

203 was determined by dichromate titration and S03 by precipitation in an acid solution after removal of the ammonium hydroxide group and silica. Atomic absorption spectroscopy tech- niques were used for K20, Na20, SrO, Mn2G3

, ZnO and Cr203

. Colorimetric techniques were used to determine Ti02 and P205 while fluoride was determined by an ion selective electrode method. Loss on ignition was determined at 1000°C. In each determination duplicate measurements were made on two to ten randomly selected samples. Through

the use of various techniques (colorimetric, gravimetric, potentiometric, optical emission elements were determined to be less than 0.01 wt<%: CI, Ba, Zr, B, V, Ni, Mo, Sn, Pb, Cu, and Ag. The total of 99.97 <7o of the certified constituents in the cement corroborates the evaluation and indicates that significant biases have not been introduced. CAUTION: To obtain the most accurate results by x-ray fluorescent methods of analysis, the user should compare his samples to the particular SRM that is most nearly the same in overall chemical composition. Alternatively, inter- element effect calibration procedures may be adopted to minimize biases.

54
U.S. Department of Commerce

MaJcoJat-Bald/ige

National Bureau of Standards

Ernest AmtHef, Director National Mmmn af Btat&arite

Certificate of Analgia

Standard Reference Material 638

Portland Cement

(Cap Color is Green)

This Standard Reference Material (SRM) is intended for use in checking chemical methods of analysis and in calibration of instrumental methods of analysis. The value listed for a constituent is the present best estimate of the "true" value based on the results of a definitive analysis program carried out in the laboratories of the Portland Cement Association by N. R. Greening, W. F. Mivelaz and R. F. Crow, with W. G. Hime of Erlin, Hime Associates acting as consultant. The certified value for a

constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported;

for a subscript figure, the deviation is not expected to be more than ±5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures.

Constituent Percent by Weight Constituent Percent by Weight CaO2 62,09 Na^ 0.13 Si02 21.

4

g SrO .07 A12Q3 4.4

5 p2o5 .06 Fe203 3.55 Mn203 .05 S03 2.34 F .04 MgOa 3.83 ZnO .10 K20 0.59 Cr203 .01 TiQ2 .25 Ign. loss • 9

5 Totalb 99.97 If the procedures of ASTM CI 14 are foliowed a small amount of CaO will remain in the MgO precipitate. In this case the uncorrected values given below for CaO and MgO should be used. CaO 62.0

5 MgO 3.8

5

b A correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross total, was determined by

multiplying the percent fluoride by the ratio- of the atomic weight of oxygen to the molecular weight of fluorine (0.421). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by B. E. Foster, R. E. Michaelis, and

C. L. Stanley. Washington, D.C. 20234 December 15, 1983 Stanley D. Rasberry, Chief

(Revision of certificates Office of Standard Reference Materials dated 2-24-77 and 6-12-74)

(Over)55
HOMOGENEITY TESTING: Measurements were made at NBS on the portland cement supplied by the Marquette Cement Corporation by S. D. Rasberry, M. M. Darr, and J. McKay by x-ray fluorescence analysis. The cement was

sampled at 16 locations and two briquettes were prepared for each one. Calcium and sulfur, chosen as key elements

for checking inhomogeneity, were determined by making four independent measurements on each briquette. A trend- elimination statistical design was employed in measuring the specimens. An analysis of these data indicated the homogeneity was satisfactory. Following these measurements the cement was thoroughly blended and packaged in hermetically sealed glass vials by personnel of the Cement and Concrete Research Laboratory and the Office of Standard Reference Materials. DEFINITIVE ANALYSIS PROGRAM OF THE PORTLAND CEMENT CORPORATION: "Wet" chemical

gravimetric methods were used for the major constituents CaO, Si0

2 , A1203 and MgO. (The methods were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe203 was determined by dichromate titration and S03 by precipitation in an acid solution after removal of the ammonium hydroxide group and silica. Atomic absorption spectroscopy tech- niques were used for K2Ot Na^, SrO, Mn203

, ZnO and Cr203

. Colorimetric techniques were used to determine Ti02 and P2Os while fluoride was determined by an ion selective electrode method. Loss on ignition was determined at 1000°C. In each determination duplicate measurements were made on two to ten randomly selected samples. Through

the use of various techniques (colorimetric, gravimetric, potentiometric, optical emission elements were determined to be less than 0.01 wt<Vo: CI, Ba, Zr, B, V, Ni, Mo, Sn, Pb, Cu, and Ag. The total of 99.97 <Vo of the certified constituents in the cement corroborates the evaluation and indicates that significant biases have not been introduced. CAUTION: To obtain the most accurate results by x-ray fluorescent methods of analysis, the user should compare his samples to the particular SRM that is most nearly the same in overall chemical composition. Alternatively, inter- element effect calibration procedures may be adopted to minimize biases.

56
U.S. Depanm«ni of Commerce

MaJcfllnrrBaidrige

:$ccretary

National Bureau of Siandaroj

Ernest Ambler. Director Nattunai Bureau uf B>tattfcari*0

(EerttftcatE af Analysts

Standard Reference Material 639

Portland Cement

(Cap Color is Clear)

This Standard Reference Material (SRM) is intended for use in checking chemical methods of analysis and in calibration of instrumental methods of analysis. The value listed for a constituent is the present best estimate of the "true" value based on the results of a definitive analysis program carried out in the laboratories of the Portland Cement Association by N. R. Greening, W. F. Mivelaz and R. F. Crow, with W. G. Hime of Erlin, Hime Associates acting as consultant. The certified value for a

constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported;

for a subscript figure, the deviation is not expected to be more than ±5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures.

Constituent Percent by Weight Constituent Percent by Weight

CaOa 65.7

6 0.65 Si0

2 21.6, SrO .15 A1

2 03 4.2

g p2o5 .08 Fe

203 2.40 Mn203 .08 S03 2.4

g F .02 MgOa ZnO .01 K20 0.06 Cr203 .01 Ti02 .32 Ign. loss 1.00 Totalb 100.16

a If the procedures of ASTM CI 14 are followed a small amount of CaO will remain in the MgO precipitate. In this case the uncorrected values given below for CaO and MgO should be used. CaO 65.

3 MgO 1.2,

b A correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross total, was determined by

multiplying the percent fluoride by the ratio of the atomic weight of oxygen to the molecular weight of fluorine (0.421). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by B. E. Foster, R. E. Michaelis, and

C. L. Stanley. Washington, D.C. 20234 December 15, 1983 Stanley D. Rasberry, Chief

(Revision of certificates Office of Standard Reference Materials dated 2-24-77 and 6-12-74) (Over) 57
HOMOGENEITY TESTING: Measurements were made at NBS on the portland cement supplied by the Centex Ce- ment Corporation by S. D. Rasberry, M. M. Darr, and J. McKay by x-ray fluorescence analysis. The cement was

sampled at 16 locations and two briquettes were prepared for each one. Calcium and sulfur, chosen as key elements

for checking inhomogeneity, were determined by making four independent measurements on each briquette. A trend- elimination statistical design was employed in measuring the specimens. An analysis of these data indicated the homogeneity was satisfactory. Following these measurements the cement was thoroughly blended and packaged in hermetically sealed glass vials by personnel of the Cement and Concrete Research Laboratory and the Office of Standard Reference Materials. DEFINITIVE ANALYSIS PROGRAM OF THE PORTLAND CEMENT CORPORATION: "Wet" chemical

gravimetric methods were used for the major constituents CaO, SiO-,, AI

2 03 and MgO. (The methods were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe

2 03 was determined by dichromate titration and S03 by precipitation in an acid solution after removal of the ammonium hydroxide group and silica. Atomic absorption spectroscopy tech- niques were used for K.,0, Na-,0, SrO, Mn-,03

, ZnO and Cr203

. Colorimetric techniques were used to determine TiO, and P~,0

5 while fluoride was determined by an ion selective electrode method. Loss on ignition was determined at 1000°C. In each determination duplicate measurements were made on two to ten randomly selected samples. Through

the use of various techniques (colorimetric, gravimetric, potentiometric, optical emission elements were determined to be less than 0.01 wt%: CI, Ba, Zr, B, V, Ni, Mo, Sn, Pb, Cu, and Ag. The total of 100.l6<7o of the certified constituents in the cement corroborates the evaluation and indicates that significant biases have not been introduced. CAUTION: To obtain the most accurate results by x-ray fluorescent methods of analysis, the user should compare his samples to the particular SRM that is most nearly the same in overall chemical composition. .Alternatively, inter- element effect calibration procedures may be adopted to minimize biases.

58
S. Departm^ik of Commerce Malcolar&aldnge

,|5ecfelary|' National pur«>iol Standards

Ernest l^nib^r. Director Rational ^mtnn af jitanrlartte

Certificate of (Analysis

Standard Reference Material 1880

Portland Cement

(Cap Color is Black)

This Standard Reference Material (SRM) is intended for use in evaluating chemical methods of analysis and in the

calibration of instrumental methods of analysis. SRM 1 880 consists of three sealed vials of type 1 Portland cement, each

containing approximately 5 grams. The certified value listed for a constituent is the present best estimate of the "true" value based on the results of a

definitive analysis program carried out in the laboratories of the Portland Cement Association. The certified value for a

constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported; for a subscript figure, the deviation is not expected to be more than ± 5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures. Constituent Percent by Weight Constituent Percent by Weight CaOa 63.1 4 Na2 0 0.28 Si02 19.82 SrO .06 AI2O3 5.O3 P2O5 .29 Fe2 03 2.91 Mn203 .08 SO3 3.37 F .10 MgOa 2.69 CI .02 K2O 0.91 ZnO .01 TiQ2 .23 Ign. loss 1.38 Total

b 100.28

*If the procedures of ASTM CI 14 are followed, a small amount of CaO will remain in the MgO precipitate. In this case

the uncorrected values given below for CaO and MgO should be used: CaO 63.05 MgO 2.75

b A correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross

total, was determined by multiplying the percent fluoride by the ratio jf the atomic weight of oxygen to twice the atomic

weight of fluorine (0.421). Correction of the total for the small amount of chloride was negligible (<0.0I%). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by R.K. Kirby. Stanley D. Rasberry, Chief

Office of Standard Reference Materials Washington, DC 20234 February 10, 1984

(over) 59
Acknowledgements The preparation of this material and the coordination of technical measurements leading to certification were performed under the direction of H.M. Kanare of the Chemical/ Physical Research Department, Portland Cement

Association (PCA), Skokie, Illinois. The cement was ground and blended with the aid of C. Wilk, J. Leonard, and

H. Love. The packaging operations were performed by E. LaBonde, J. Loneard, M. McCann, C. Palmiano, and

C. Wilk. Homogeneity testing was performed by C. Palmiano. The definitive analyses were conducted by R. Crow,

E. LaBonde, and H. Seiler.

Preparations

This SRM was blended from equal parts of Type I Portland cement supplied by the St. Mary's Cement Company in Canada and the Texas Cement Company. Before blending, each cement was ground in an impact mill until all particles were between 0.5 and 45 /im as selected with an air classifier. The size distributions of the two cements, as determined

with a sedimentation apparatus, were quite similar. Tests indicated that after 6 1/2 hours of blending the mix was homogeneous.

Homogeneity Testing Following the packaging of the cement in hermetically sealed glass vials the homogeneity was determined by measuring

36 samples selected in a stratified random process. X-ray fluorescence analysis was used to determine the differences in calcium, sulfur, and iron by four replicate measurements on each briquette.

Definitive Analysis "Wet" chemical gravimetric methods were used for the major constituents CaO, SiC»2, AI2O3 and MgO. (The methods

were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe2C>3 was determined by dichromate titration and SO3 by

precipitation in an acid solution. Atomic absorption spectroscopy techniques were used for K2O, Na20, SrO, Mn203

and ZnO. . Colorimetric techniques were used to determine TiCh and P2O5. Fluoride was determined by an ion selective electrode method and chloride was determined by a potentiometric titration method. Loss on ignition was determined at 1000 °C. In each determination duplicate measurements were made on three to ten randomly selected samples. Through

the use of various techniques (colorimetric, gravimetric, and AAS) the presence of the following trace elements were

determined to be less than 0.01 wt. %: Ba, Zr, B, and Cr. The total of 100.28% of the certified constituents in the cement

corroborates the evaluation and indicates that significant biases have not been introduced. Caution To obtain the most accurate results by x-ray fluorescence methods of analysis, the user should compare his samples to the

particular SRM's that are most nearly the same in overall chemical composition. Alternatively, interelement effect calibration procedures may be adopted to minimize biases.

60
^National ^uram of ^tanrfards

Certificate of ^nal^st*

Standard Reference Material 1881

Portland Cement

(Cap Color is White)

This Standard Reference Material (SRM) is intended for use in evaluating chemical methods of analysis and in the

calibration of instrumental methods of analysis. SRM 1881 consists of three sealed vials of type I Portland Cement,

each containing approximately 5 grams. The certified value listed for a constitutent is the present best estimate of the "true" value based on the results of a definitive analysis program carried out in the laboratories of the Portland Cement Association. The certified value

for a constituent is not expected to deviate from the "true" value by more than ± 1 in the last significant figure reported; for a subscript figure, the deviation is not expected to be more than ± 5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than those uncertainty figures. Constituent Percent bv Weight Constituent Percent by Weigh CaOa 58.6? Na20 0.04 Si02 22.2s SrO 11 AI2O3 4.16 P2O5 0.09 Fe203 4.68 Mn203 0.26 SO3 3.6s F 0.09 MgOa 2.63 CI 0.01 K20 1.17 Ign. loss 2.01 TiQ2 0.2s Totalb 100.04 ZnO 0.01

If the procedures of ASTM CI 14 are followed, a small amount of CaO will remain in the MgO precipitate. In this case the uncorrected values given below for CaO and MgO should be used: CaO 58.65 MgO 2.70 b

\ correction has been made for the amount of fluoride present. This correction, which was subtracted from the gross total, was determined by

multiplying the percent fluoride by the ratio of the atomic weight of oxygen to twice the atomic weight of fluorine (0.421). The technical and support aspects involved in the preparation, certification, and issuance of this Standard Reference

Material were coordinated through the Office of Standard Reference Materials by R.L. McKenzie.

Gaithersburg, MD 20899 Stanley D. Rasberry, Chief December 7, 1987 Office of Standard Reference Materials

(Revision of certificate dated 2-10-84)

(over)

61
Acknowledgements The preparation of this material and the coordination of technical measurements leading to certification were performed under the direction of H.M. Kanare of the Chemical/ Physical Research Department, Portland Cement

Association (PCA). Skokie, Illinois. The cement was ground and blended with the aid of R. Monger. The packaging

operations were performed by M. McCann, R. Monger, C. Palmiano, and C. Wilk. Homogeneity testing was performed

by J. Leonard and C. Palmiano. The definitive analyses were conducted by R. Crow and H. Seiler.

Preparations This SRM was blended from a Portland cement supplied by the Portland Cement Association and 5 wt. %of Terra Alba gypsum. Before blending, the cement was ground in an impact mill until all particles were smaller than 40 pm as selected with an air classifier and the gypsum was ground in a steel-ball mill to pass a 200-mesh sieve (<75/im). Tests indicated

that after blending the mix was sufficiently homogeneous.

Homogeneity Testing Following the packaging of the cement in hermetically sealed glass vials the homogeneity was determined by measuring

36 samples selected in a stratified random process. X-ray fluorescence analysis was used to determine the differences in calcium, sulfur, and iron by four replicate measurements on each briquette.

Definitive Analysis "Wet" chemical gravimetric methods were used for the major constituents CaO, SiOi, AI2O3 and MgO. (The methods

were essentially those of ASTM CI 14 using a 0.5-g sample.) Fe:Ch was determined by dichromate titration and SO3 by

precipitation in an acid solution. Atomic absorption spectroscopy techniques were used for K2O, Na20, SrO, MniOi

and ZnO. Colorimetric techniques were used to determine TiO: and P2O5. Fluoride was determined by an ion selective electrode method. Loss on ignition was determined at 1000 °C. In each determination duplicate measurements were made on three to ten randomly selected samples. Through the use of various techniques (colorimetric, gravimetric, and A AS) the presence of the following trace elements were determined to be less than 0.01 wt. %: Ba, Zr, B, CI, and Cr. The

total of 100.04% of the certified constituents in the cement corroborates the evaluation and indicates that significant biases have not been introduced. Caution To obtain the most accurate results by x-ray fluorescence methods of analysis, the user should compare his samples to the

particular SRM's that are most nearly the same in overall chemical composition. Alternatively, interelement effect calibration procedures may be adopted to minimize biases.

62
Appendix B Summaries of the homogeneity tests for SRMs 633 634

635

636

637 638

639 1880 1881

are given in this appendix.

The tests on the "600 series" cements were made by measuring the variation of calcium and sulfur with normal x-ray fluorescence methods using the "1000 series" cements as standards. The packaged vials of each cement were stored in

15 or 16 cans and two vials were taken from each can totaling 30 or 32 specimens. Each specimen were prepared by briquetting. All of these specimens were satisfactory except one from SRM 639 which proved to be defective and was not included in the results. The following tables indicate the average value

of four measurements for each element on each specimen. The run- order of the measurements used a trend elimination sequence. Because an analysis on the two vials from each can did not indicate they were "duplicates", each vial was considered to be an independent sample. The tests on SRMs 1880 and 1881 were made by measuring the variation of calcium, sulfur, and iron with normal x-ray fluorescence methods. Thirty-six

vials of each cement were selected in a stratified random process from the cases in which they were stored. A specimen from each vial was prepared by

briquetting and four measurements were made for each element. Using one of the specimens as a machine standard, the others were measured using a trend elimination sequence. The following tables indicate the average value of four measurements for each element on each specimen.

63
SRM 633 CaO

64 95% by wt. 64 87% by wt

64 97 65 09 64 90 65 09 64 98 65 06 64 97 65 02

65 01 64 99 64 92 65 19 65 06 65 00

65 06 64 93 65 03 65 02 64 88 65 04

65 05 64 91

65 01 64 99 64 95 64 97 65 03 65 05 64 96 65 05 Average 65.00% by wt

.

Std. Dev. 0.069% by wt

.

Coef. of Var. 0.105%

S0 3 2 181% by wt. 2 206% by wt

2 180 2 191

2 215 2 229

2 208 2 208

2 196 2 232

2 218 2 214

2 194 2 176

2 177 2 189

2 197 2 200

2 192 2 203

2 202 2 195

2 194 2 202

2 192 2 190

2 189 2 209

2 205 2 217

2 178 2 221 2.200% by wt. 0.015% by wt. 0.67%

SRM 634 CaO

63 20% by wt. 63 21% by wt

63 16 63 22

63 19 63 29 63 29 63 13 63 21 63 29 63 13 63 18 63 18 63 14

63 12 63 20

63 22 63 22 63 22 63 23

6 3 09 63 23 63 15 63 12

63 25 63 22

63 23 63 17 63 21 63 33 63 13 63 25 Average 63.20% by wt

.

Std. Dev. 0.057% by wt

.

Coef. of Var. 0.091%

S0 3 2 180% by wt. 2 183% by wt

2 200 2 194

2 181 2 189

2 200 2 192

2 193 2 196

2 180 2 199

2 203 2 211

2 204 2 220

2 195 2 201

2 212 2 191

2 191 2 227

2 227 2 193

2 213 2 206

2 204 2 195

2 215 2 205

2 194 2 204 2.200% by wt. 0.012% by wt. 0.56%

64
SRM 635 CaO S0 3 59 . 54% by wt

.

59 ,47% by wt. 6 .795% by wt. 6

.

, 827% by wt

59 . 72 59

,

, 80 6 . 778 6

.

. 803

59 . 90 59 , 69 6 . 774 6

.

. 777

59 . 73 59 , 78 6 . 814 6 . 798

59 . 88 59 . 83 6 .748 6 . 772

59 . 65 59

,

. 79 6 . 803 6 . 814

59 .70 59 .59 6 .842 6 .794

59 .69 59,.71 6 .782 6 .837 59 ,68 59 .72 6 .803 6 .835 59 .67 59,,68 6..776 6..824

59 ,62 59,,53 6..778 6,.824

59 ,61 59,,73 6 .870 6 .779 59 .67 59,,70 6 .752 6 .820 59 .78 59,,64 6 .778 6 .845

59,,68 59,,76 6 .774 6 .804

59 ,77 59,,72 6 .784 6,.798 Average 59.70% by wt

.

Std. Dev. 0.094% by wt

.

Coef. of Var. 0.158%

6.800% by wt. 0.028% by wt. 0.40%

SRM 636 CaO S0 3 63,,91% by wt. 63.,89% by wt. 2. 193% by wt. 2. 189%

63,,81 64,,20 2. 178 2. 180

63,,94 63,.74 2. 158 2. 209

63,.76 63,,85 2. 192 2. 213

63,.84 63,,69 2.,195 2.,220

63 .82 63 ,91 2,,179 2,,213 63 .75 63 ,81 2,,206 2,,191 63 ,80 63 .87 2 ,203 2 .196 63 .77 63 .74 2,,206 2 .198 63 ,78 63 .63 2 ,201 2,.212 63 .66 63 .68 2 ,199 2 .213 63 .72 63 .62 2 .224 2 .225

63 .74 63 .85 2 .183 2 .160

63 .84 63 .83 2 .217 2 .236

63 .74 63 .81 2 .183 2 .230 Average 63.80% by wt

.

Std. Dev 0.111% by wt

Coef. of Var. 0.176%

2.200% by wt, 0.019% by wt 0.82%

65
SRM 637 CaO SO3

66, 34% by wt. 66,,48% by wt. 2,,428% by wt. 2..397%

66..36 66..47 2,,407 2,,401

66,,40 66 .39 2 .399 2,.405

66,. 37 66 .45 2 .392 2 .420

66 ,44 66 .54 2 .391 2 .407 66 .27 66 .40 2 .404 2 .406 66 .35 66 .22 2 .415 2 .412 66 .42 66 .46 2 .385 2 .387 66 .53 66 .27 2 .407 2 .398 66 .46 66 .32 2 .401 2 .394

66 .54 66 . 30 2 .382 2 .403 66 .52 66 . 30 2 . 399 2 . 398

66 .40 66 .49 2 .381 2 .401

66 .39 66 .42 2 .402 2 .378

66 . 35 66 .34 2 .400 2 .400 Average

Std. Dev. Coef. of Var.

66.40% by wt

.

0.085% by wt. 0.129%

2.400% by wt 0.011% by wt

0.47%

SRM 638 CaO S0 3 62 .15% by wt. 62 .07% by wt. 2 .400% by wt. 2 .423% by wt

62 .15 62 .24 2 .363 2 .397 62 .15 62 .00 2 .415 2 .413

62 .06 62 .12 2 .408 2 .402

62 .13 62 .10 2 .410 2 .402 61 .96 62 .09 2 .396 2 .381

62 .31 62 .17 2 .389 2 .365 62 .06 62 .15 2 .392 2 .393 62 .09 62 .02 2 .398 2 .389

62 .08 61 .98 2 .384 2 .420

62 .08 62 .14 2 .414 2 .413

61 .97 62 .10 2 .423 2 .387

62 .11 62 .06 2 .414 2 .425 62 .01 62 .21 2 .380 2 .396

62 .05 62 .16 2 .402 2 .406 Average

Std. Dev. Coef. of Var.

62.10% by wt. 0.077% by wt

0. 124%

2.400% by wt. 0.016% by wt. 0.68%

66
SRM 639 CaO SO3

66 64% by wt

c c. DO 75% by wt

z 527% by wt

z dUz

66 49 £ C DO c c DO z 475 z 66 54 C C DO D / 0z

t; 0 r\ dZU z 66 70 C C DO Di 0z cm z jUj

66 33 66 65 2 525 2 509

66 71 66 57 2 492 2 514

66 46 66 52 2 475 2 514

66 66 66 45 2 478 2 534

66 38 66 62 2 532 2 500

66 59 66 40 2 487 2 531

66 47 66 60 2 525 2 532

66 62 66 44 2 490 2 539

66 49 66 58 2 522 2 542

66 35 66 41 2 515 2 487

66 46 2 513 Average 66.50% by wt . 2.500% by wt, Std. Dev. 0.115% by wt . 0.020% by wt

Coef. of Var. 0.175% 0.79%

67
SRM 1880 CaO S0 3 Fe 2 03

63. 11% by wt. 3. 338% by wt. 2 809% by wt

63. 52 3. 332 2 814

63. 02 3 371 2 802

63 12 3 361 2 807

63 17 3 324 2 810

63 25 3 361 2 828

63 22 3 334 2 817

63 16 3 355 2 809

63 08 3 381 2 807

63 27 3 365 2 811

62 88 3 353 2 796

63 14 3 381 2 812

62 94 3 343 2 811

63 34 3 368 2 808

63 10 3 362 2 826

63 04 3 326 2 826

63 06 3 356 2 800

63 08 3 301 2 802

63 12 3 349 2 811

63 07 3 328 2 814

63 16 3 347 2 806

62 98 3 359 2 805

63 14 3 353 2 803

63 02 3 376 2 .804

63 14 3 353 2 .816

63 58 3 374 2 .818

62 89 3 358 2 .814

63 42 3 332 2 .827

63 01 3 321 2 .794

63 08 3 310 2 .803

63 18 3 360 2 .818

63 03 3 364 2 .807

63 39 3 355 2 .812

63 27 3 327 2 .804

62 84 3 327 2 .791 Average 63.14% by wt . 3.349% by wt . 2.810% by wt

Std. Dev. 0.168% by wt . 0.021% by wt . 0.0089% by wt

Coef. of Var. 0.265% 0.60% 0.32%

68
SRM 1881 CaP S0 3 Fe2Q3 60 14% by wt. 3 869% by wt. 5 007% by wt

59 99 3 681* 4 970

60 11 3 833 4 984

59 98 3 824 4 990

60 06 3 864 4 980

60 03 3 868 4 993

60 05 3 858 5 Oil

60 01 3 875 4 994

60 12 3 862 4 998

60 04 3 796 4 970

59 95 3 841 4 975

59 93 3 856 4 981

60 34 3 756 4 988

60 16 3 881 4 997

60 15 3 886 5 010

59 93 3 829 4 985

60 16 3 754 4 996

60 27 3 896 4 998

60 10 3 789 4 997

59 92 3 820 5 002

59 95 3 873 4 982

59 77 3 773 4 969

60 05 3 881 4 993

59 96 3 860 4 973

60 09 3 837 4 999

60 15 3 843 4 997

59 84 3 790 4 970

59 95 3 780 4 981

59 95 3 792 4 974

59 92 3 833 4 984

60 04 3 827 4 989

59 98 3 841 4 989

60 12 3 851 4 997

60 14 3 823 4 985

60 08 3 774 4 986 Average

Std. Dev. Coef. of Var.

60.04% by wt. 0.115% by wt. 0.193%3.833% by wt

.

0.039% by wt. 1.02%

4.988% by wt

.

0.0116% by wt. 0.23%

*Value not included in the statistics.

69
Appendix C Results of the Cooperative Test Program for the Chemical Analysis of SRMs 633 through 639 PARTICIPATING LABORATORIES Atlantic Cement Co. P.O. Box 3 Ravena, NY 12143 Methods (W,F,J) Ash Grove Cement Co. 640 Southwest Blvd. Kansas City, KS 66103 Methods (X,A)

California Portland Cement Co. P.O. Box 947 Colton, CA 92324 Methods (W,F,A)

Capitol Cement

P.O. Box 412 San Antonio, TX 78218 Methods (W,A)

Department of the Army

Waterways Experiment Station

Corps of Engineers

P.O. Box 631 Vicksburg, MS 39180 Methods (W,F)

Pacific Western Ind., Inc. P.O. Box 1247 Lebec, CA 93243 Methods (W,A,C)

Penn-Dixie Cement Corp.

P.O. Box 152 Nazareth, PA 18064 Method (X) Portland Cement Association

5420 Old Orchard Road

Skokie, IL 60077 Methods (W,J,A,C)

Southwestern Portland Cement Co. P.O. Box 937 Victorville, CA 92392 Method (X) St. Mary's Cement Co. Ltd.

P.O. Box 68 Bowmanville, Ontario

Canada Methods (W,F,C)

Marquette Cement

20 North Wacker Drive

Chicago, IL 60606 Methods (W,F,C)

Universal Atlas Cement Buffington Station

Gary, IL 46401 Methods (J,F)

National Bureau of Standards Analytical Chemistry Division

Gaithersburg, MD 20899 Method (X)

70
A summary of the results of the cooperative test program is given in Table C. The complete data of this program as reported by William G. Hine of Erlin, Hine Associates is available from the National Bureau of Standards, Office of Standard Reference Materials. The code for the' methods used in this program

are as follows: A Atomic Absorption

C Colorimetry

F Flame Photometry

J Jugovic

W Wet X X-Ray Fluorescence

The deviations reported in the table were determined by

where x^ are the n individual measurements made on each of the seven cements and xcert are the final certified values for that component. The ranges are determined by

. i max i min

The values for the deviations and ranges for SO3 as determined by x-ray

fluorescence do not include the values obtained on SRM 635

(-7% SO3) for which the deviations reached 1.8%. A copy of the preliminary certificate that was based on the results of this program is also provided.

71
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73
S. Department of Commerce

Frederick B. Dent

Secretary

National RicnardW.Ro^ta,

Bureau of Standards

Director ^^1X^X011

^Srf X* t *TK3 ^VLTWVL 01f JZ' tit ^13*183^8

(Eeritficaie of (Attaints

Standard Reference Materials 633-639

Portland Cements

These SRM's are fine powders and are intended for use both in checking chemieal methods of

analysis and in calibration with instrumental methods of analysis. SRM No. 633 634 635 636 637 638 639 CAP COLOR RED GOLD BLUE YELLOW PINK GREEN CLEAR

Constituent Percent by Weight

Al 2°3 3.7 4 5.2 6.2 3.1 3.3 4.5 4.3 CaO 64. r0

62. 659.8

63.r0

66.nu 62.! 65.8 MgO i.o 4 3.4 4.0 0.7 2 3.8 4

1.29 Ti0 2 0.24 0.30 0.32 0.17 .21 0.25 0.31

Si0 2 21.9 20.7 18.5 23.2 23.1 21.4 21.6 S0

3

°> 1 0 1 7.0 2.3 2.3.3 2.3 2.4 p 2o5 0.24 0.10 0.17 0.09 0.25 0.06 0.08 Mn203 .04 .28 .09 .12 .06 .05 .08 K20 .165 .43 .45 .57 .245 .59 .05 Na20 .6 4 .14 .07 .10 .13 .12 • 6 r SrO .31 .12 .22 .04 .10 .07 .15 4.2 2.87 2.65

ile2

1.8 0 3.5 8

2.4 2

Ign. loss 0.7

5

1.6

i 3.25 Li* 1.6 8 0.9 5

1.0 Total 99.95 99.91 99.97 99.97 99.93 99.8 l a 100. 13

a One laboratory reported 0.11 ZnO in this SRM, thus increasing the total to 99.92%. PRELIMINARY CERTIFICATION: This Certificate is "preliminary" because additional analytical work is planned that will improve the accuracy of some of the values listed. The value listed for a constituent is the present hest estimate of the "true" value based on the results of the analytical program. The values are not expected to deviate from the "true"

1 values by more than ±1 in the last significant figure reported; for subscript figures, the deviation is not expected to be more than ±5. Based on the results of homogeneity testing, maximum variations within and among samples are estimated to be less than the uncertainty figures given above. Washington, D.C. 20234 J. Paul Cali, Chief June 12, 1974 Office of Standard Reference Materials 74
Appendix D Letter sent to members of ASTM Committee C-l soliciting their help in selecting

the new SRMs

.

75
Dear ASTM Member: Two new portland cement chemical standard reference materials are being

produced by the Portland Cement Association for the National Bureau of Standards. These will supplement the seven samples currently available from

NBS (SRM 633-639)

.

We would like to know what chemical composition you think these new standard

cements should have. For your reference, we have attached a copy of the Certificate of Analysis for SRM 633-639. Please write your suggestions for proposed cement standards below the certified values, and return to: Howard Kanare

NBS Cement Standards Project

Portland Cement Association

5420 Old Orchard Road

Skokie, Illinois 60077 We would appreciate your reply before March 15, 1981. Thank you for your suggestions

.

Sincerely,

R. F. Gebhardt

Chairman

C-01.23 on Chemical Analysis

76
Appendix E List of Equipment and Packaging Materials Used in Preparing SRMs 1880 and 1881. Vortec Impact Mill, Model M-l Vortec Air Classifier, Model C-14 Micromeritics Sedi-Graph Particle Size Analyzer

Paul 0. Abbe Steel -Ribbon Blender, Model 7 Mateer-Burt Auger-Type Power Filler, Model 31 -A Kimble Type III Flint-Glass Flat-Bottom Shell Vial

(15-mm O.D. x 45-mm height)

TLB Plastics Corp. High-Density Polyethylene Cap

(fits one dram shell vial)

Kimble Type III Flint-Glass Flat-Bottom Shell Vial

(19 -mm O.D. x 100-mm height) Glass Fiber Pad (Filter Disc)

(12.5-mm dia. x 0.5-mm thick) Flame Sealing Machine (NBS Property)

Rigaku XRF Spectrometer, Model 3064 X-Rays: 40-kv, 70-mA water-cooled rhodium target tube fitted with

a Rh-plated beam defining cone. Sample: Pressed powder briquet, 30 x 3 mm in aluminum cap, pressed

at 50,000 psi, spining sample holder with 25-mm diameter

copper mask.

Element Crystal Line Detector

Counting

Time Typical CountsPer Measurement

Ca LiF(200) K FPC* 20 sec. 510,000

Fe LiF(200) K SC 40 sec. 260,000

S Ge K FPC* 20 sec. 240,000

*Flow Proportional Counter with P-10 gas at 0.05 scfh. Cardboard Shipping Boxes and Trays (285 vials per tray)

77

Appendix F Some miscellaneous information is provided in this ap'pendix including values

for the Blaine surface area given in Table Fl

.

79
Table Fl . Blaine Surface Area*

SRM Average n Std Dev

633 3015 cm2 /g 3 32 634 3485 3 144

635 4840 3 122 636 3609 3 88 637 5678 3 134

638 3735 3 49 639 3356 3 76 1016 3305 3 46

*Data reported by Norman H. Suhr of the Pennsylvania State University.

Table F2 . Chemical Analysis of the SRM 1880 Cements Before Blending,

% by wt.

CaO SiC- 2 AI2O3 Fe.223 SO3 MgO K2Q Na2 Q

Cement A 61.31 20.25 4.30 3.12 3.73 4.33 0.98 0.58 Cement B 64.24 19.63 5.64 2.86 3.21 1.13 0.91 0.13 NOTE

:

All analyses by x-ray fluorescence

80

Appendix G Flexible Packaging Study*

The intent of this study was to determine if modern flexible packages could preserve the properties of cement. Such packages are widely used for the storage of foodstuffs, medicine, and electronic equipment.

The potential advantages of flexible packages include:

(1) high speed filling and sealing;

(2) low-volume storage compared to glass;

(3) reduced weight;

(4) reduced breakage in shipping and handling;

(5) ease of shipping through automated labelling; and

(6) ease of identification through prelabelling

.

Water vaporproof flexible packages generally are composed of several laminations of different materials, each serving a specific function. A schematic of a typical laminated film is shown in Figure Gl . These layers can

be coextruded (dry lamination) or, more commonly, attached

(inner surface)

THIN LAYERS OF

ADHESIVE OR

THERMOPLASTIC

RESIN

(outer surface)

HEAT SEALABLE FACE

(.001")

( Polyethylene, polypropylene)

.00035 in. Al FOIL EXTERIOR SUBSTRATE

( .003")

(Kraft paper, polyolefin, mylar)

Figure Gl. Schematic of typical laminated film with thin layers of adhesives. The outer substrate provides mechanical

strength, abrasion resistance, and a surface for labelling. The aluminum foil

is the actual barrier to moisture and gas transmission. The heat - sealable face can be any number of thermoplastic materials, usually polyethylene,

polypropylene, or a proprietary plastic film.

^Conducted by PCA under contract to NBS

.

82
The plan of this investigation was to encase portland cement samples in various

types of commercially available flexible packages and then test them under

average conditions including heat, moisture, high CO2 , and mechanical abuse. The contents of the packages would then be analyzed for changes by measuring

properties such as specific surface area and ignition loss. The packages would

be examined for degradation, including maceration, delamination , splitting or cracking, and discoloration. A commonly used military specification (MIL-B-131E) was considered as a general

guide to the testing of the flexible packages. This specification lists the required physical properties for a packaging material to be qualified as a "water vaporproof, flexible, heat-sealable , barrier material". However, the determination of the maximum permissible water vapor transmission rate (WVTR)

as required in this specification would not be an acceptable test for the protection of cement. Therefore, modifications of the test procedures were imposed to evaluate the various types of flexible packages under extremely

adverse conditions.

Eight types of flexible packaging films were made available for testing. Six

to twelve pouches were made from each film, filled with approximately 15 g of Portland cement, and heat sealed. The descriptions of the packets are given in Table Gl. One or two samples of each type of package were placed into each of the environmental chambers listed below:

A. Fog Room (73 °F and 100% R.H.). Packages placed on a wire mesh

shelf.

B. High C02 Atmosphere (73 °F, 71% R.H., and 100% C0 2

)

.

Packages placed on a wire mesh shelf above saturated (SrCl2*6H20) solution

inside a 3-liter glass jar. Note: This humidity is nearly the optimum for carbonation of cement.

C. Hot Room (100 °F and 20% R.H.). Packages placed in loosely covered cardboard box.

D. Cold Room (0 °F). Packages placed in loosely covered cardboard box. Packages remained in these chambers for 14 to 28 days. They were then removed

and inspected. The packages that did not appear badly degraded were then opened and the cements were tested for ignition loss in accordance with ASTM

C114. Tests for specific surface area using the Blaine Air Permeability

apparatus were found to be not sensitive enough to serve as an indicator of changes in cement properties.

83
Table G-l. Description of Flexible Packages as Received

Outer

ID# Substrate

Inner Sealing

Film

1 Saran/nylon Saran/nylon Polyethylene

2 White Kraft paper Foil Polyethylene

3 Brown Kraft paper Foil

4 Tyvek <TM>

Polyolef in

7 Gold lacquer/

Myl ar (TM)

Foil

5 Brown Kraft paper

6 Mylar <TM> Foil/

Mylar (TM)

8 White Kraft paper Foil

Polyethylene

Polyethylene

Polyethylene

Polyethylene

Metallized Polyethylene

nylon

Surlyn^TM)

Empty

Package

Weight

(3-l/2"x5"V

2- 5 g

3- 1 g

4.4 g

3.9 g

2- 7 g

3.4 g

1.4 g

3- 9 g

Appearance

Smooth, transparent

fairly flexible

Semi-gloss, smooth, opaque, stiff Matte finish, opaque, stiff

Opaque, white,

semi-gloss, stiff Matte finish, opaque fairly flexible

Silver, glossy, opaque, fairly,

stiff

Glossy, gold, opaque , very

flexible

Semi-gloss, opaque, fairly stiff

aFor reference, an empty glass vial and cap as used for the cement

SRMs weighed about 14.0 g.

84
Table G-2. Appearance of Packages After Tests Package ID Test A (Fog Room)

1 Severe delamination of Saran; all- around edge curl; slight discoloration

Test C (Hot Room) Test D (Cold

Slight edge curl; Appearance as slight discoloration received

Slight maceration; very slight edge

curl; no delamination

Appearance as received Very slight e curl Some staining; no edge curl; some wrinkles no delamination

Appearance as received Appearance as received

Appearance as received Appearance as received Appearance as received

Slight maceration; some staining: some wrinklingAppearance as received Appearance as received

Appearance as received Appearance as received Appearance as received

Major edge curl; severe delamination

of gold-lacquered top layer

Slight edge curl All-around ed curl Minor edge curl, some wrinkling

no discoloration

Appearance as received Moderate edge

85
Selected packages from Test C (Hot Room) were opened and the cement extracted with hot CHCI3 using a procedure previously developed at PCA. The weights of

the CHCI3 - soluble residues were determined and their infrared spectra were

recorded.

To measure resistance to physical abuse, selected packages were attached to a high-speed vibrating table (Syntron Jogger J-lA) for about six hours. The two sides of the packages were then separated by cutting just inside all four

seams, and the inner surfaces were rubbed together with cement in between to abrade the heat- sealable films. These inner surfaces were then cleaned by

swabbing with alcohol, and examined by scanning electron microscopy. A glass

vial containing cement was similarly vibrated and examined for comparison.

The appearances of the packages after removal from test chambers A, C, and D are given in Table G2 . Packages 1 and 7 were badly delaminated after Test A. All other packages appeared good although the paper layers were slightly

macerated. Ignition losses were measured for all packages after removal from

test chamber A following two days of drying at 73 °F and 40% R.H. The results

of these tests are given in Table G3 . After analyzing these results and considering their appearance, Packages 1, 3, 5, and 7 were eliminated from further consideration. Table G3. Effect of High Humidity

Package Ignition Loss Package Ignition Loss Control 0 ,72% by wt. 5 1. 37% by wt.

1 2..00 6 0. 71

2 0..71 7 0. 89

3 0..99 8 0. 67

4 0,.72

Packages 2, 4, 6, and 8 were removed from test chamber B and after drying,

ignition losses were determined. See Table G4

.

Table G4 . Effect of High C02 Atmosphere

Package Ignition Loss

2 0.66% by wt

.

4 0.68

6 0.72

8 0.68

All of these packages appeared to prohibit carbonation of the cement under the conditions of the test, and should therefore be considered good barriers to the transmission of moisture and CO2 at room temperatures. Packages having

polyethylene and Surlyn^TM) as the inner heat sealable surface were removed

from test chamber C and conditioned at 73 °F and 40% R.H. for two days before

the cement was extracted with CHCI3. The weights of the CHCI3 - soluble residues

are given in Table G5 . Infrared spectra of the top two residues indicated only

hydrocarbons in the cements, typical of trace residues found in commercial

86
Portland cements. The infrared spectrum of the residue from Package 8 was

complex, indicating the presence of short chain esters and amides. These are degradation products of the polymer and the "slip additive" which permits

manipulation of Surlyn^^^ by high-speed machines. Table G5 . Effect of Hot Environment

Package Residue

Control 0.006%

3 0.005

8 0.020

Packages of types 2 and 8 along with a glass vial of SRM 114n were subjected to the vibration and abrasion tests previously described. The external appearance

of all three types of containers was unremarkable after the vibration test. Before testing, both the polyethylene and glass had very smooth surfaces showing only minor topography at moderate magnification. The Surlyn^M) had a cratered appearance that turned out to be caused by the mirror-pocket casting

rollers used in extruding this material. After testing and cleaning with

alcohol the inner surface of the polyethylene was deformed and cement particles

remained on the surfaces of both the smooth glass and the cratered Surlyn^TM) , but the plastic surface held many more particles than the glass surface. Packages that had an aluminum foil vapor barrier and a polyethylene heat- sealable face performed well. The appearance of the Kraft paper substrates were slightly affected by the fog room exposures although the contents were preserved. The plastic substrates (Packages 4 and 6) gave the best external appearance after all tests. These plastic films (Mylar and Tyvek^TM)) also provide superior strength and external abrasion resistance; however, the Kraft paper substrates may accept and retain a printed label better than the plastic. The smoothness of the polyethylene inner surfaces allowed easy discharging of

the samples, although some cement was difficult to remove from the seams. The rough surface of the Surlyn^TM) trapped some of the smaller particles, which

could not be removed even with camel-hair brushes and swabbing. Coupled with

the problem of the organic residue found in the cement, it is not recommended

the Surlyn^TM) be used as a heat-sealable inner liner.

87
Conclusions and Recommendations

Flexible packages made of laminated barrier materials containing pinhole -free aluminum foil and having polyethylene film as the sealing material were found

to protect hygroscopic cement from hydration and carbonation. However, several factors mitigate against the use of these packages for cement:

(1) Chemicals in or on the surfaces of the plastic films can contaminate the cement

.

(2) Sealing the packages is critical and should be performed with an automated sealing machine, which requires considerable capital investment. Cements may also interfere with proper sealing.

(3) Cement sticks to the inner surfaces of the flexible packages. Thus not all of the sample can be removed from its container and some segregation may

occur

.

(4) Manufacturers of the packaging films generally agree that the films will

retain their initial properties for several years, but they will not guarantee them for as long as ten years

.

(5) It is concluded that at this time flexible packages are not reliable for cement SRMs that may be in storage for ten or more years before use.

88
NBS-114A 'rev. 2-sc

1. PUBLICATION OR 2. Performing Organ. Report No. 3. Publ i cation Date BIBLIOGRAPHIC DATA

SHEET (See instructions)

" REPORT NO. SJBS/SP-260/110 February 1988

4. TITLE AND SUBTITLE Standard Reference Materials: Portland Cement Chemical Composition Standards

(Blending, Packaging, and Testing)

5. AUTHOR(S)

R. Keith Kirby and Howard M. Kanare

6. PERFORMING ORGANIZATION (If joint or other than NBS. see instructions) NATIONAL BUREAU OF STANDARDS

U.S. DEPARTMENT OF COMMERCE

GAITHERSBURG, MD 20899

7. Contract/Grant No.

8. Type of Report & Period Covered Final

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street. City, State, ZIP) Same as item 6

.

10. SUPPLEMENTARY NOTES Library of Congress Catalog Card Number 88-600503

[~J Document describes a computer program; SF-185, FlPS Software Summary, is attached.

11. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant bibliography or literature survey, mention it here) Standard Reference -Materials of portland cement are intended for use in evaluating chemical methods of analysis and in calibrating instrumental methods

of analysis such as x-ray fluorescence and atomic absorption spectroscopy. The first cement SRMs, numbers 177, 1011, 1013, 1014, 1015, and 1016, are no longer

in stock. SRMs 633, 634, 635, 636, 637, 638, 639, 1880, and 1881 have been produced to replace the first series. This paper describes the blending, packaging,

homogeneity testing, and the detailed analysis of the chemical composition for

the certification of SRMs 633-639 and 1880 and 1881.

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolons) blending; chemical analysis; homogeneity testing; Standard Reference Materials;

x-ray fluorescence

13. AVAILABILITY

Unl imited Q F° r Official Distribution. Do Not Release to NTIS

fcjj Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF PRINTED PAGES 99

USCOMM-DC 6043-P80

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area. Often serve as a vehicle for final reports of work performed at NBS under the sponsorship of other government agencies. Voluntary Product Standards—Developed under procedures published by the Department of Commerce in Part 10, Title 15, of the Code of Federal Regulations. The standards establish nationally recognized re- quirements for products, and provide all concerned interests with a basis for common understanding of the

characteristics of the products. NBS administers this program as a supplement to the activities of the private

sector standardizing organizations. Consumer Information Series—Practical information, based on NBS research and experience, covering areas of interest to the consumer. Easily understandable language and illustrations provide useful background

knowledge for shopping in today's technological marketplace. Order the above NBS publications from: Superintendent of Documents, Government Printing Office, Washington, DC 20402. Order the following NBS publications—FIPS and NBSIR 's—from the National Technical Information Service, Springfield, VA 22161.

Federal Information Processing Standards Publications (FIPS PUB)—Publications in this series collectively constitute the Federal Information Processing Standards Register. The Register serves as the official source of

information in the Federal Government regarding standards issued by NBS pursuant to the Federal Property and Administrative Services Act of 1949 as amended, Public Law 89-306 (79 Stat. 1127), and as implemented by Executive Order 11717 (38 FR 12315, dated May 11, 1973) and Part 6 of Title 15 CFR (Code of Federal

Regulations). NBS Interagency Reports (NBSIR)—A special series of interim or final reports on work performed by NBS

for outside sponsors (both government and non-government). In general, initial distribution is handled by the sponsor; public distribution is by the National Technical Information Service, Springfield, VA 22161, in paper copy or microfiche form.

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