P.1 

OAR Box 1846 

Prepped by Ollie Stewart 

Document Number: 

72) ll-J-15 

Docket Number: 

A-90-07 

Printed 11/18/2008 7:30:17 AM Sheet 72 of 93 
A -30-00 

H-J - J5" 

CRC Report No. 551 

i>' r 

f_'.? ^ 

\Ar' 

CHEMICAL METHODS FOR THE 

MEASUREMENT OF 

UNREGULATED DIESEL EMISSIONS 

Carbonyls/Aldehydes 

Particulate Characterization 

Sulfates 

PAH/N02PAH 

August 1987 

COORDINATING RESEARCH COUNCIL, INC. 

219 PERIMETER CENTER PARKWAY, ATLANTA, GEORGIA 30346 
P.3 

COORDINATING RESEARCH COUNCIL 

INCORPORATED 

2 1 9 PERIMETER CENTER PARKWAY 

ATLANTA. GEORGIA 3034 6 

(404) 396-340 0 

CHEMICAL METHODS FOR THE MEASUREMENT OF 

UNREGULATED DIESEL EMISSIONS -

CARBONYLS/ALDEHYDES 

PARTICULATE CHARACTERIZATION 

SULFATES 

PAH/NO2PAH 

(CRC-APRAC PROJECT NO. CAPI-1-64) 

IN FORMULATING AND APPROVING REPORTS, THE 

APPROPRIATE COMMITTEE OF THE COORDINATING 

RESEARCH COUNCIL, INC. HAS NOT INVESTIGATED 

OR CONSIDERED PATENTS WHICH. MAY APPLY TO 

THE SUBJECT MAHER. PROSPECTIVE USERS OFTHE 

REPORT ARE RESPONSIBLE FOR PROTECTING THEMSELVES AGAINST LIABILITY FOR INFRINGEMENT OF 

PATENTS. 

Prepared by the 

Chemical Characterization Panel 

of the 

CRC Program Group on Composition of Diesel Exhaust 

Edited By: 

J. M. Perez 

R. E. Jass 

D. G. Leddy 

August 1987 

Air Pollution Research Advisory Committee 

of the 

Coordinating Research Council, Inc. 
P.4 

*. .

 T 

1 t 

TABLE OF CONTENTS 

Page 

SECTION I - INTRODUCTION 3 

SECTION II - HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC (HPLC) 

DINITROPHENYLHYDRAZINE (DNPH) METHOD FOR CARBONYL COMPOUNDS 

A. Scope 7 

B. Definition 7 

C. Experimental 7 

D. Sample Collection 9 

E. Sample Analysis 9 

F. Precision and Accuracy 10 

G. Alternate Sampling Procedure 11 

SECTION III - DIESEL PARTICULATE CHARACTERIZATION 

A. Purpose 15 

B. Summary 15 

C. Definitions/Abbreviations 16 

D. Experimental 17 

SECTION III.l - TOTAL PARTICULATE MASS 

A. Procedures 21 

B. Measurement of Total Particulate Mass 23 

SECTION 111.2 - SOLVENT EXTRACTABLE FRACTIONS (SEF) 

A. Scope 27 

B. Extraction of SOF 27 

C. Extraction of TOE 28 

D. Determination of Sulfate 29 

E. Combined Water 30 

F. Repeatabi 1 ity 31 

SECTION IV - NITRATED POLYCYCLIC AROMATIC HYDROCARBONS 

A. Scope.... 33 

B. Background 33 

C. Definitions/Abbreviations 33 

D. Experimental Equipment 33 

E. Sol vents 34 

F. Procedure 34 

G. Precision and Accuracy 35 

H. Alternate Column Configuration 35 

I. Alternate Method 35 
P,5 

SECTION V - POLYCYCLIC AROMATIC HYDROCARBONS 

A. Scope 39 

B. Background 39 

C. Definitions/Abbreviations 39 

D. Equipment. 40 

E. Sol vents 40 

F. Procedures 41 

REFERENCES 49 

TABLES 

Table I - Physical Properties of Carbonyl Compounds 55 

Table II - Storage Stability 56 

Table III - Comparison of SOF and Vacuum Removal of Organic 

Fraction 57 

Table IV - Elution of Polycyclic Aromatic Hydrocarbons on 

a Bondapak NH2 Column 58 

Table V - High Performance Liquid Chromatography of Polycyclic 

Aromatic Hydrocarbons: Fraction 1 59 

Table VI - High Performance Liquid Chromatography of Polycyclic 

Aromatic Hydrocarbons: Fraction 2 60 

Table VII - High Performance Liquid Chromatography of Polycyclic 

Aromatic Hydrocarbons: Fraction 3 61 

FIGURES 

Figure 1 - Sampling Cart (Schematic Diagram) 62 

Figure 2 - Carbonyl Analysis Method 63 

Figure 3 - Chromotogram of the Standard DNPH-Aldehyde Mixture.... 64 

Figure 4 - Formaldehyde Stability 65 

Figure 5 - Acrolein Stability 66 

Figure 6 - Total Aldehyde Stability 67 

Figure 7 - Soxhlet (Photograph) 68 

Figure 8 - Mass of Bound H?0 Per Gram H0SO4

 in an A Queou s 

Solution Versus Relative Humidity (25°C) 69 

Figure 9 - Schematic of Nitropyrene Analysis System 70 

Figure 10 - HPLC PAH Method No. 1 71 

Figure 11 - HPLC Method Summary - Fractionation of the 

Diesel Extract 72 

Figure 12 - HPLC PAH Method No. 2 73 

Figure 13 - Typical HPLC Traces, Method No. 2 74 

APPENDICES 

APPENDIX A - Membership: Chemical Characterization Panel of the 

CRC Diesel Exhaust Composition Group A-1 

• n -
P.6 

• . . f 

SECTIO N I 

INTRODUCTION 
P.7 

-3-

I . INTRODUCTION 

This Progress Report summarizes research conducted on unregulated 

diesel emissions methods by the Chemical Characterization Panel (CCP) 

of the Coordinating Research Council's (CRC) Diesel Composition Group 

over the past three years. (Membership of the Chemical Charactization 

Panel is liste d in Appendix A.) Methods are recommended for the 

measurement of aldehydes/carbonyls, sulfates, particulate characterization, polycyclic aromatic hydrocarbons (PAH) and nitrated PAH (N02-

PAH). Most of the methods proposed are the result of cooperative 

testing and are considered to be based on sound engineering practices. 

Two of the methods, PAH and N02PAH, are stil l being evaluated through 

cooperative round-robin study. 

The PAH method was developed under CRC contract at IITRI and previously evaluated in a round-robin by the group. Currently, a followup international round-robin is in progress. 

The NO2PAH method has evolved primaril y as the result of work conducted at EPA-RTP. An alternate method was developed by A. D. Little , 

Inc. under contract for the CRC-APRAC CAPE-30 Project Group. 
P.8 

i. . ' 

SECTIO N I I 

HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC (HPLC) 

DINITROPHENYLHYDRAZINE (DNPH) METHOD FOR CARBONYL COMPOUNDS 
P.9 

I I . HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC (HPLC) DINITROPHENYLHYDRAZINE (DNPH) METHOD FOR CARBONYL COMPOUNDS 

A. SCOPE 

The procedure incorporates an improved 2,4-dinitrophenylhydrazine 

method in which Cj to Cg carbonyl compounds are collected by 

bubbling diesel exhaust or diluted diesel exhaust through an 

acetonitrile solution of DNPH reagent and analyzed by HPLC using 

UV detection at 365 nm. Using an acetonitril e solution for 

sample collection allows direct injection of the sample into the 

HPLC, thereby eliminating many of the recovery steps and saving 

considerable sample preparation manhours. The method results in 

quantitative sample recoveries, improved accuracy and provides 

for a simple, rapid and low cost method for aldehyde analysis. 

The method was reported

 (1)*. 

B. DEFINITION 

Carbonyl Compounds - Compounds containing the C=0 functional 

chemical group. This procedure refers to C^ to Cg compounds 

containing this group, specifically the compounds shown in Table 

I. The method could also be applicable to higher molecular 

weight carbonyl compounds. 

EXPERIMENTAL 

1. Reagents - Reagents used in thi s procedure should be HPLC 

Grade (distilled in glass) or Equivalent Grade Solvents as 

indicated: 

Acetonitril e - Burdick and Jackson Labs, Inc., Fisher 

Scientific Co., J.T. Baker Chemical Co. or equivalent. 

2,4-Dinitrophenylhydrazine - Aldrich Chemical Co. or J.T. 

Baker, recrystallized twice from HPLC grade methanol or 

acetonitrile. 

Distilled, deionized water (HPLC Grade). 

2N HCl - Best Source. 

Ethanol - Best Source. 

Perchloric Acid - Best Source. 

* Numbers in ( ) are references at end of text. 
P.10 

• 8 -

Aldehyde Standards - Individual aldehydes for standard 

preparation should be best available grade. 

2,4-DNPH Derivatives - Method of preparation discussed in 

later section. 

2. Equipment 

HPLC with UV detection (365 nm). Various units are available. 

5 u Zorbax ODS 4.6 mm x 25.0 cm HPLC column, DuPont Inst. Co. 

Midget Impingers (Light-Duty Diesels) or 100 mL Glass Impingers (Heavy-Duty Diesels). 

Flowmeter, pump and meter -- required for sample collection 

(Figure 1). 

LC syringes as required. 

Melting Point Apparatus. 

3. Pretest Preparation 

a. Aldehyde-DNPH Derivatives - The 2,4-DNPH derivatives are 

prepared by reaction of the individual aldehydes with a 

saturated DNPH solution in 2N HCL. The derivatives are 

filtered, washed with 2N HCl and HoO, air dried, and 

stored in sealed vials. Purity of the derivatives is 

checked by melting point determinations, Table I. 

Purity can be improved by recrystallization from 

absolute ethanol or methanol, if required. Individual 

derivatives or a mixture of the standards should also be 

checked for purity by HPLC. 

b. Preparation of Solutions and Standards - A 6.25vmole/mL 

of 2,4-DNPH stock solution is prepared by addition of 

100 mL of acetonitrile to 120 mg of purified DNPH 

crystals. Dilution of the stock solution with acetonitrile is used to prepare a 1.6 mole/mL DNPH absorbing 

solution in the bubblers. Five drops of IN HC104 

catalyst is added per each 20 mL of absorbing solution. 

The acid is added just prior to use. 

Standard solutions of the aldehydes are prepared by 

injecting 5.0 mL of the aldehyde into a septum sealed 

vial containing 5.0 mL of acetonitrile. The concentrations of the stock solutions are calculated from the 

densities of the aldehydes. The formaldehyde concentration is determined by the concentration of the 
P.11 

formalin solution by titration. Standard derivative 

solutions are prepared by injecting 2.0 to 20 yL of the 

aldehyde solution into a septum sealed vial containing 

the derivatizing reagent. Weighing solid DNPH hydrazones and dissolving them in acetonitrile can also be 

used to prepare standard derivatives. 

D. SAMPLE COLLECTION 

1. Samplinq System - The sampling system can vary depending on 

the source of aldehydes. One system, Figure 1, was designed 

to sample diluted exhaust from various size dilution tunnels 

or heated Teflon

 R bags containing diluted exhaust. For 

sampling directly from undiluted exhaust streams a short 

(approximately 2 meters X 0.635 cm O.D.) stainless steel 

line should be added to allow some cooling of the exhaust 

prior to entering the Teflon coated heated line. 

2. Sampling - A 1.6ymole/mL DNPH solution is used for emission 

testing. This is obtained by diluting the stock solution as 

indicated above or the solution can be prepared by dissolving about 31 mg of purified DNPH in 100 mL of acetonitrile. 

For each light-duty diesel (LDD) sample to be taken, the 

impingers are prepared by adding 10 mL of the DNPH solution 

and 2 drops (approximately 100 yL) of the IN HC104 to each 

impinger. Samplers are connected in series and placed in an 

ice bath. For sampling heavy-duty diesels (HDD), 20 ml of 

the DNPH solution with 4 drops IN HC104 are added to each 

impinger. Sample flow through the bubblers is maintained at 

1/2 L/min for LDD and 2-4 L/min HDD. Normally 10-30 L of 

exhaust (100-300 L at 9:1 dilution ratio) is adequate to 

obtain sufficient sample for a reliable analysis depending 

on the type of emission source. The lower the source concentration the more sample that is required for good quantitative results. As a guideline, aldehyde levels from 

LDD<HDD<HD gasoline engines. 

Samples should be analyzed immediately or refrigerated until 

used. 

E. SAMPLE ANALYSIS 

1. Analysis Procedure - Samples should be analyzed as soon as 

possible, preferably within a few hours, to minimize the 

losses of certain species. The procedure for analysis is 

shown in Figure 2. Following an acceptable HPLC blank, the 

calibration standards are run. 
P.12 

-10-

An example of an HPLC trace for the standards is shown in 

Figure 3. It should be emphasized that the appearance may 

vary depending on the HPLC system utilized. However, the 

relative retention times of the peaks should closely agree 

with those shown in Table I. If not, retention times should 

be redetermined using a set of standards. The time required 

from injection to the appearance of the internal standard, 

benzaldehyde, is considered to be 1.0. The times for all 

other peaks to elute are normalized to it. If an automated 

' system is utilized, the samples can be sequenced running a 

standard check at the end of the series or every 4-6 samples 

depending on the number of samples to be analyzed. 

2. Sample Stability - The stability of samples indicates that 

losses of individual aldehydes, with the the exception of 

acrolein, are only about 10 percent in 24 hours. Experimentally determined losses for formaldehyde, acrolein and total 

aldehydes are shown in Figures 4, 5, and 6. The acrolein 

losses as demonstrated on Figure 5 are concentration dependent. Higher concentrations approach 35% loss in 24 hours. 

Fortunately, this species is normally a minor component of 

the total aldehydes. Total aldehyde losses are 10 percent 

or less. Typically, sampling and analysis is completed 

within 24 hours. Storage stability beyond 24 hours is shown 

on Table II. The data show that losses in total aldehydes 

within an eight week period were less than 5 percent. This 

is primarily due to acrolein and crotonaldehyde degradation. 

F. PRECISION AND ACCURACY 

The method precisio n and accuracy were determined in a 

cooperativ e round-robi n conducted by the Chemical 

Characterization Panel of the Diesel Exhaust Composition inhouse 

Group of the Coordinating Research Council, Inc., Air Pollution 

Research Advisory Committee (CRC-APRAC CAPI-1-64). The results 

are described in Reference 1. The concentration levels of 

aldehydes in the study are considered to be a worst case 

situation involving low levels of aldehydes. Reproducibility, 

i.e., agreement within a laboratory, was better than 20 percent 

relative standard deviation (r.s.d.). Agreement between laboratories , repeatability , was as high as 35 percent r.s.d. The 

precision and accuracy improved as the concentration of aldehydes 

in the samples increased. The concentration levels in the CRC 

study were of the order of 0.02y moles/ml and should be considered minimum levels required to achieve 20 percent r.s.d. 

reproducibility. With experience and analysis of samples within 

24 hours after collection, a precision and accuracy of 10 percent 

r.s.d. or better should be achievable. 
P.13 

•11-

G. ALTERNATE SAMPLING PROCEDURE 

Both General Motors Research and EPA-RTP have developed procedures utilizing DNPH-coated silica cartridges for sampling and 

analyzing carbonyl compounds in engine exhaust. S.B. Tejada's 

(EPA-RTP) method was presented at the CRC workshop in March 

1985(2). Basically, the procedure involves: 

1. Reagent purification. 

2. Preparation of DNPH-coated silica cartridges. 

3. Impinger solution. 

4. Cartridge sampling. 

5. HPLC conditions. 

One interesting aspect of this method is the presence of an 

unidentified "compound-x" that may be the decomposition product 

of acrolein in air. 

A second advantage of this procedure is the ability to readily 

collect field samples. Stability of formaldehyde and acrolein 

appear improved on the cartridge. 

Tejada's procedure and the method for preparing cartridges have 

been published in the literature*3 5. 
P.14 

SECTIO N II I 

DIESEL PARTICULATE CHARACTERIZATION 
P.15 

-15-

III. DIESEL PARTICULATE CHARACTERIZATION 

A. PURPOSE 

These procedures are intended for use in the collection and 

characterization of particulate emissions from diesel engines. 

They may be used as a guide toward standard practices so that 

results from various sources may be compared with some degree of 

accuracy. It should be kept in mind that the procedures that 

follow may be subject to change to keep pace with experience and 

technical advances. The procedures cover A) Total Particulate 

Mass, B) Solvent Extractable Fractions, C) Sulfates and Combined 

Water, D) PAH and N02PAH. 

B. SUMMARY 

In the procedures described, the particulates are collected on 

preweighed, TeflonR coated, glass fiber filters. The total 

particulate mass 1s determined by weighing the filters before and 

after use. The filters are extracted with dlchloromethane in a 

Soxhlet unit, dried and weighed again to give the mass of the 

soluble organic fraction. The filter is next extracted with a 

water solution by agitation and the sulfate is determined by ion 

exchange chromatography. The mass of solid material in the 

particulate is determined by subtracting the mass of sulfate and 

soluble organic fraction from the total particulate matter. PAH 

and NOoPAH analyses are conducted on the soluble organic fraction, variations of these procedures are in use depending on the 

objectives of the test(1). 

The NOoPAH procedure is found in Section IV. The PAH method is 

found in Section V along with a short PAH analysis version useful 

for screening samples. A vacuum sublimation method useful in 

measuring Residual Carbonaceous Particulate on a number of 

samples simultaneously is described in Section III.2B(i). 

The mass rate of each component is calculated by dividing the 

mass of the component collected by the cubic meters of exhaust 

sampled, the kilowatt-hours of work done, the distance traveled, 

or on a specific fuel consumption basis. The particulate emission results can be expressed in mass units of grams per cubic 

meter of exhaust, grams per kilowatt-hour, grams per mile, or 

grams per kilogram of fuel consumed. 
P.16 

16-

C. DEFINITIONS/ABBREVIATIONS 

Total Particulate Mass (TPM) - Particulate collected on a Teflon 

coated glass fiber filter at temperatures between 52°C and 

45°C. 

Solvent Extractable Fraction (SEF) - This fraction contains the 

material that can be extracted from the total particulate 

mass by various solvents and contains both organic solvent 

and inorganic solvent extracts. 

Soluble Organic Fraction (SOF) - The solvent extractable fraction 

of total particulate mass removed by Soxhlet extraction 

using d1 chloromethane (see note, page 17). 

Total Organic Extract (TOE) - The fraction of the total partlculate mass removed by Soxhlet extraction using a 

toluene:ethanol binary solvent (32:68 wt/wt, B. Pt 76.7°C) 

system. 

Water Soluble Sulfates (Sulfates) - The major extractable inorganic fraction in the particulate sample is the water 

soluble sulfate fraction. These are those sulfates removed 

by agitation of the particulate sample in a water solution 

and analyzed directly by ion chromatography. The water 

solution contains 60/40 isopropyl/water alcohol, or newer 

ion chromatograph procedures use only the chromatographic 

eluant for the extraction solution. 

Combined Water (Water) - This 1s water that is chemically combined with sulfuric add and metallic sulfates in the particulate material. It amounts to about 1.3 times the mass 

of measured sulfate

 (1 '2

»

3 )

 when the TPM is equilibrated at 

50X relative humidity at 20°C. 

Residual Carbonaceous Particulate (RCP) - This fraction 1s the 

calculated particulate remaining after removal of the total 

organic extract fraction, sulfates, and combined water. The 

residual "carbon" fraction may contain a small amount of 

sulfur and metals: 

RCP=TPM - TOE - SULFATES - WATER. 
P.17 

1 — •'• • 

-17-

D. EXPERIMENTAL 

1. Reagents - Solvents should be high purity, distilled in 

glass or equivalent: 

a. 

b. 

c. 

d. 

Dichloromethane (Methylene Chloride) 

NOTE: Should only be used in a laboratory hood with 

adequate ventilation(6). 

Toluene 

Ethanol 

Distilled, deionized water 

2. Equipment - Best Source Available 

a. 

b. 

c. 

d. 

e. 

f. 

gh. 

i. 

j. 

k. 

Filters - Pallflex TX40HI20WW or equivalent, 47mm to 

102 mm diameter (T60A20 filters are also used. However, 

higher extractable levels are obtained from T60A20 blank 

filters than TX40HI20WW filters. If T60A20 filters are 

used, batches should be checked for extractables.) 

Filter holder* 

Pump and metering system* 

Timer* 

Millipore Filter cassettes or Petri dishes 

Soxhlet Extractor with boiling flask and reflux condenser 

Microbalance capable of reading to + 0.01 mg 

Constant temperature and humidity chamber or room 

Rotary evaporator 

Kuderna-Danish Evaporator 

Yellow lighting for room (no wavelengths below 500 nm) 

1. Filter Forceps 

m. Ultrasonic bath 

* Components of particulate collection system which may vary with 

respect to individual system design. 
P.18 

SECTIO N III. l 

TOTAL PARTICULATE MASS 
P.19 

•21-

III. 1 TOTAL PARTICULATE MASS 

A. PROCEDURES 

1. Operation of the Engine - Diesel particulate can be collected in a variety of tests. For steady-state particulate 

collection with or without a dilutio n tunnel, the engine 

operating procedures as described in SAE Procedure J1003(7) 

are guidelines for engine operation. For transient tests , 

the USEPA procedures^ can be used as a guideline. 

Dilution Ratio - The dilution ratio used to collect particulate is normally about 10-20 to 1, Air to Exhaust. In 

practice, the actual dilution ratio is usually determined by 

the incoming exhaust temperature and the amount of air 

required to achieve a 125°F (52°C) or lower filte r temperature. The time to collect a desired mass of particulate is 

also a factor in selecting the dilution ratio. References 9 

and 10 discuss these Interactions. Normally, the C02 levels 

of the raw exhaust and diluted exhaust, corrected for CO2 in 

the incoming air , are used to calculate dilutio n ratio in 

steady-state tests. Mass flow measurements are usually used 

in transient tests to determine the dilution. 

The dilutio n rati o can also be determined from the 

concentration of N0X in the raw and diluted exhaust. 

3. Tunnel Background - Tunnel background and conditioning can 

affect the levels of some specific hydrocarbon species such 

as PAH. The tunnel background is normally not a major 

factor in tota l particulate and SOF measurements i f some 

simple precautions are taken. Tunnel blanks should be 

periodically run by drawing dilution air through the filte r 

for an equivalent period of time as that used for sampling. 

Background levels should be well under IS of the total mass 

expected to be collected. On start-up of a test , engine 

exhaust conditions (e.g., temperature, FID emissions) should 

be stabilized* 1 1 '

1 2 1

 before introducing the exhaust into the 

tunnel. A1r only should be run through the tunnel during 

engine warm-up. A minimum of 20 minutes at the desired 

dilutio n rati o should be allowed for tunnel equilibration 

before collecting samples. I f the sampling point follows a 

high hydrocarbon emissions point (e.g., Low Idle or ligh t 

load conditions), a 15-minute high load burnout of the exhaust system may be desirable prior to setting the engine 

test condition. 
P.20 

•22-

4. Particulate Collection Particulate collection methodology 

lefined in the USEPA procedures*5for transient tests is defined in the USEPA pi '. 

For steady-state measurements, the methodology can be considerably different depending on the type of dilution tunnel 

used* 13,14 '. The procedures used are usually those that 

have been developed by the researcher. The particulate 

characterization methods discussed in the following section 

do not depend on how the sample was collected. However, 

several precautionary items that will improve reproducibility in a laboratory are as follows: 

(a) Utilize Pallflex TX40HI20WW filters . (Filter sizes 

from 47mm to 102mm are commonly used.) 

(b) Handle the filte r at all times using tweezers or 

forceps. Avoid using fingers on the filter s or any 

device that may tear particles from the filter. 

(c) Condition the filter by allowing it to equilibrate in a 

constant temperature and humidity environment for 16-24 

hours prior to collection of the sample. After 

sampling, the filters should be conditioned in the same 

environment prior to weighing. Room temperatures 

should not vary more than 20°+3°C during conditioning. 

The humidity, during conditioning, should be between 

30% and 70S and be controlled to a range of +102. 

(d) The filte r shall be weighed to the nearest 0.01 mg just 

prior to use. 

(e) Monitor the AP across the filte r during sampling. A 

AP greater than 13 cmHg is excessive and the termination of the test should be considered. In no case 

should the AP exceed 25 cmHg. 

(f) It is preferable to collect as large a sample in as 

short a time as possible. Sample times of 20 - 40 

minutes are common. The mass per filter as listed are 

minimums desired: 

Filter Size, Minimum Mass 

mm mg 

47 1 

70 2 

90 3.5 

102 5 

At light particulate loads longer collection times may 

be required. 
P.21 

•23-

(g) Filter face velocities of 10-20 cm per second are 

suggested. 

(h) Two or three blank filter s from each lot of filter s 

should be chosen at random and then subjected to the 

SOF and sulfate analyses described in Section III . 

Normally the values for SOF on these blanks will be 

less than 0.1 mg and sulfates should be below detection 

limits. 

(1) Two blank filter s from each lot of filter s should be 

selected at random and stored in the constant temperature and humidity chamber or room. Each day the 

filter s can be weighed and recorded. Additional 

filter s loaded with standard particulate (NBS STD 

Reference Material 1650) or sulfuric add may be more 

sensitive to changes. The weight can be compared to 

previous day's values and can serve as an indicator of 

the performance of the environmental chamber. 

B. MEASUREMENT OF TOTAL PARTICULATE MASS 

1. After the sample is obtained as per Section III.1A-4, 

place the filte r in the constant temperature and humidity 

chamber or room and allow to equilibrate in the dark or 

under yellow light for 16-24 hours. As an option, see the 

following section (III.1B-2). 

Place the filter in a vacuum desiccator saturated with NH4OH 

for one hour. As an option, evacuate the desiccator with a 

water aspirator or vacuum pump (approximately 20 mm vacuum) 

and allow ammonia gas to leak into the desiccator until it 

is at atmospheric pressure. Let the filte r sit in the 

ammonia atmosphere for 15 minutes, and displace the ammonia 

from the desiccator with air. Place the filte r in the 

constant humidity chamber for 16-24 hours. 

If the NH4OH procedure is used, the combined water correction in Section III.2-E does not apply since water is 

removed during the equilibration. This method is useful in 

handling samples containing high sulfate levels. It 

stabilizes the weight at about one mole of water per mole of 

sulfate*155. 

3. Remove the filters from their containers with filter forceps 

and weigh to the nearest 0.01 mg. Record the weight. 
P.22 

-24-

4. The difference in weight between the first weighing of the 

filter and the weighing in step 3 is the TPM, if ammoniation 

is not used. If the ammoniation is used, the weight added 

by the addition of two mole equivalent weights of NH4 for 

each mole of sulfate must be subtracted from the TPM mass. 

5. For long term storage the filter is returned to the cassette 

or Petri dish, wrapped in aluminum foil and stored in a 

freezer at -20°C. When the filter is removed from the 

freezer it should be re-equilibrated for 24 hours and reweighed to see if any losses in TPM occurred during storage. 

If losses exceed 10 wt. % of the TPM or 20 wt. % of the SOF, 

discard the values. 
P.23 

SECTIO N III . 2 

SOLVENT EXTRACTABLE FRACTIONS (SEF) 
P.24 

•27-

III.2 SOLVENT EXTRACTABLE FRACTIONS (SEF) 

A. SCOPE 

The methods of collection of a particulate sample from light duty 

diesel vehicles and heavy duty diesel engines are specified by 

USEPA procedures*8'. These samples are collected directly from 

diesel exhaust or from dilution tunnels using specific engine 

operating and sampling procedures and are composed of various 

subfractions described in the next section. These fractions are 

of interest in evaluating health effects issues and effects of 

engineering or technology changes in the engine systems. Particulate samples can be obtained at transient or steady-state 

conditions depending on the purpose of the test. 

SEF fractions discussed include, SOF, TOE, Sulfate and Combined 

Water. 

B. EXTRACTION OF SOF - This fraction is obtained by extraction with 

dichloromethane (see note on page 17). 

1. Procedure 

(a) Carry out all operations under "yellow light" and minimize exposure to sunlight. Otherwise, keep the samples 

in the dark. 

(b) Fold the filter in halves, and finally quarters and/or 

eights with the particulate to the inside. Bend over 

the top of the filte r before the final fold. Use the 

filter forceps and wear gloves and avoid tearing fibers 

from the filter. Carry out the filte r folding on a 

clean, plate glass surface. Place the filter s in the 

Soxhlet extractor with the point of the fold towards 

the base of the extractor. 

(c) Assemble the Soxhlet apparatus as illustrated in 

Figure 7. For 47 mm filter s a micro Soxhlet unit 

equipped with a 30 ml flat bottomed flask is used. Put 

20 ml of dichloromethane in the flask. Wrap the flask 

and Soxhlet unit in aluminum foil . Start the water 

flowing through the condenser. Larger flasks and condensers may be required for large filters. 
P.25 

-28-

(d) Start the hot plate or place the Soxhlet units in 

constant temperature bath and allow the solvent to 

begin cycling through the apparatus. Adjust the temperature so that the solvent cycles through the extraction cell about every 5-10 minutes. Extract for at 

least four hours. 

Cycle time of the extractors may vary. A total of 40 

cycles should be used as a guideline. 

(e) Turn off the heat, or remove from bath, and allow the 

solvent to stop boiling. 

(f) Disassemble the Soxhlet apparatus and carefully remove 

the filter with filter forceps. Place the filter on a 

clean watch glass or Petri dish and allow the dichloromethane to evaporate in a fume hood. Avoid tearing 

fibers from the filter. After 30 minutes at room 

temperature the filter can be covered or placed back in 

the plastic cassette and returned to the constant temperature and humidity chamber. Remove the cover and 

let the filter equilibrate for 16 to 24 hours. 

(g) The filter is then removed from Its container and 

reweighed on the micro-balance to the nearest 0.01 mg. 

(h) The loss of weight after this extraction is the SOF. 

(i) Vacuum sublimation 1s a possible alternative to this 

method if the SOF is not required for further analyses. 

The filters are held in a vacuum oven at 200°C and 15-

30 in. Hg pressure or less. After 16 hours carefully 

release the vacuum and remove the filters. The filters 

are then allowed to cool and are placed in the weighing 

room to equilibrate for 16 to 24 hours. Data to support this have been reported*16'. Data found in Table 

III Indicate shorter times can be used. Additional 

study of this option 1s needed. 

A disadvantage of the vacuum sublimation technique is 

that the fraction evaporated is lost and cannot be 

further analyzed. 

C. EXTRACTION OF TOE 

This fraction contains the more polar organics and is extracted 

using a toluene:ethanol binary solvent (32:68 wt/wt, B. Pt 

76.7°C). The fraction contains material that is not removed by 

MeCl2 and is equal to the SOF plus the additional material. 

Depending on the purpose of the extraction the entire fraction 

can be removed in one step, bypassing the SOF extraction. 
P.26 

•29-

NOTE: The toluene:ethanol solvent may also remove some of the 

sulfates. Therefore, sulfate analysis should not be conducted on 

filters after a TOE extraction. 

D. DETERMINATION OF SULFATE 

The filter from the SOF determination may be used to determine 

sulfates or a separate filter may be used. If enough TPM has 

been collected for an accurate analysis, sufficient sulfate will 

have been collected. Basically, the procedure involves extraction of the water soluble sulfates and analysis by ion chromatography. Instrument operating procedures are supplied by the 

manufacturer*17'. 

1. Place the filter in a 4 oz. Teflon capped bottle and add 20 

ml of an aqueous solution that is 0.003 molar in NaHCOo and 

0.0024 molar in Na2C03. Distilled, deionized water should 

be used. Some older units using older column technology may 

use a 60/40 isopropyl alcohol/water solution for extraction. 

Shake bottles vigorously or place the bottles in a sonication bath with 1-inch of water in the bottom. Shake or 

sonicate until the filter breaks up or for 10 minutes. 

3. Filter the sample through a 0.45 ym filter on a Luer fitted 

syringe filter. 

4. Calibrate an ion chromatograph with a standard potassium 

sulfate solution to obtain a calibration curve. 

5. Inject the filter sample directly into the ion chromatograph 

or dilute with the eluent if sulfate concentrations are too 

high. 

6. Compare the response from the filter sample to the calibration curve. 

7. Calculate the mg of sulfate on the filter and relate the 

results to the volume of exhaust sampled. 
P.27 

•30-

E. COMBINED WATER 

1. The preferred method is to equilibrate in the weighing room 

at 501 humidity and subtract 1.3 times the weight of sulfate 

from the TPM. An alternate method is found in following 

section 2 and 3. Corrections for other humidities can be 

determined from Figure 8. 

2. An option is to place the filter (in its container with the 

top removed) into a desiccator containing Dr1er1te for 16 

hours, remove and weigh rapidly. Subtract this weight and a 

1-mole weight of water equivalent times the moles of sulfate 

from the gross weight obtained for the TPM. 

3. If the ammoniation method, III.IB-2 , is used, subtract a 

weight equal to 0.2 of the sulfate from the TPM to correct 

for the added ammonia. (The stoichiometry suggests 2 moles 

of ammonia per mole of sulfate, however, experimental data 

[Reference 15] Indicate only about a 20 wt.% increase is 

obtained.) 

F. REPEATABILITY 

The precision of the measurement of TPM, SOF, TOE and sulfate 

will depend upon the total mass of each component collected with 

higher masses producing better precision. A CRC round-robin 

interlaboratory program has established a relative standard 

deviation of +15% for a minimum sample of 1 mg for SOF and TOE. 

For samples of 10 mg and larger, precision within a laboratory 

should be +10% or less. A round-robin was conducted and the 

results reported*18'. 

Precision of the sulfate measurement has not been established but 

it 1s expected to be +5% or better. 
P.28 

SECTIO N I V 

NITRATED POLYCYCLIC AROMATIC HYDROCARBONS 
P.29 

-33-

IV. NITRATED POLYCYCLIC AROMATIC HYDROCARBONS 

A. SCOPE 

This procedure defines the system and analytical method for the 

measurement of nitrated polycyclic aromatic hydrocarbons in 

diesel particulate samples by their conversion to amines and 

detection by fluorescence. 

B. BACKGROUND 

The determination of N02PAH compounds described in this procedure 

is based on an analytical method developed by S. Tejada at the 

U.S. EPA-RTP laboratory*2'. The method was initially developed 

for the analysis of 1-nitropyrene (1-NOP) and is currently undergoing cooperative round-robin testing. The method is an HPLC 

method and uses a Pt/Rh catalyst to convert the N02PAH to amines 

on column. The amines are then analyzed using fluorescence 

detection. 

C. DEFINITIONS/ABBREVIATIONS 

N02PAH — Nitrated Polycyclic Aromatic Hydrocarbons 

1-NOP — 1-Nitropyrene 

HPLC — High Performance Liquid Chromatograph 

Pt/Rh — Platinum/Rhodium 

D. EXPERIMENTAL EQUIPMENT 

HPLC — Various units are available. 

Columns — 1. Pt/Rh catalyst coated on 5 ym Sperisorb 5AY 

alumina.* (Available from Johnson-Mattey, Inc., 

Malvern, PA). Two columns (typical 5 cm x 4.6 mm) 

are required. 

* CAUTION - Methanol must be flushed from the column with water every 

time an end fitting is removed. (The catalyst has been observed to 

flame spontaneously when allowed to dry in air after use of an MeOH 

rich aqueous solution.) 
P.30 

-34-

2. Zorbax ODS (25 cm x 4.6 mm ID) DuPont Company, 

Wilmington, Delaware 

3. Zorbax ODS (15 cm x 4.6 mm ID) 

Fluorescence Detector — 360 nm excitation; 430 nm emission 

A schematic of the system is shown in Figure 9. 

E. SOLVENTS 

Methanol (MeOH) - Use distilled in glass quality or equivalent. 

Dlchloromethane (MeCl2) - Use distilled in glass quality or 

equivalent. (See note on page 17.) 

Distilled, deionized water 

F. PROCEDURE 

The N02PAH do not fluoresce but can be converted on column in the 

HPLC to amines which do fluoresce. This method is currently one 

of two being evaluated by the CCP. The method was recently 

utilized in the CRC-APRAC CAPE-33-80 Project conducted by 

SwRI*19'. 

1. The system utilizes two short reduction catalyst columns. 

The first one removes oxygen containing compounds from the 

solvent. The second catalyst converts the NOoPAH to fluorescent NH2PAH. The HPLC oven is set at 80°C for the 

columns. 

2. Two 5- m Zorbax ODS analytical columns are also used. The 

firs t column separates any NH2PAH present in the extract 

from the N02PAH before they enter the reduction catalyst. 

The second analytical column further separates the reduced 

N02PAH from other Interfering compounds in the extract. 

3. The appropriate extract or SEF fraction is dissolved in a 

50:50 mixture of MeCl2 and MeOH. The actual volume of 

solvent used depends on the N02PAH levels expected. Initially use 1 ml of each solvent and dilute appropriately. 
P.31 

•35-

4. The flow rate of the mobile phase is set at 1 ml/min with 

the first solvent (77% MeOH/23% water). 

5. Following the elution of the desired reduced N02PAH, e.g., 

1-NOP elutes at about 30 minutes after injection, the solvent flow is changed to pump #2 and 100% MeOH is used to 

clean the columns. After about 20 minutes, the column flow 

is switched back to pump #1 and the columns are equilibrated 

for 20 minutes prior to injection of the next sample. (See 

caution in Section IV-D.) 

6. Samples are quantified against standards obtained from the 

National Bureau of Standards*20'. The NBS standards can 

also be incorporated as internal standards. 

G. PRECISION AND ACCURACY (Round-Robin in Progress) 

Estimated +20% or better. 

H. ALTERNATE COLUMN CONFIGURATION 

If interference or peak separation problems do occur, the column 

system can be modified as described by Tejada*21'. Tejada's 

column system is more complicated but does eliminate the overlap 

of some peaks. 

I. ALTERNATE METHOD 

A gas chromatography (GC) method utilizing an election capture 

detector (ECD) was developed by A.D. Little, Inc. under contract 

for CRC-APRAC CAPE-30. The method is reported in the 

literature* 2 2 '. The method has been used by some CCP members. 

However, they did replace the splitless injection of the sample 

with on-coluran injection of the sample to obtain better results. 
P.32 

SECTIO N V 

POLYCYCLIC AROMATIC HYDROCARBONS 
•39-

POLYCYCLIC AROMATIC HYDROCARBONS 

A. SCOPE 

This procedure defines the system and analytical method for the 

measurement of polycyclic aromatic hydrocarbons in diesel particulat e samples by high performance liquid chromatography. 

B. BACKGROUND 

The analysis of PAH compounds in diesel exhaust and N02PAH compounds have received considerabl e attentio n relativ e to the 

healt h issues associated wit h diesel particulate. Two methods 

are discussed in thi s section . The firs t method evolved as a 

result of cooperative effort s of the CCP. However, the method is 

manpower intensive, requirin g some 10-12 HPLC runs to analyze 

each sample. The method uses a normal phase chromatographic 

extract cleanup followe d by an analysi s using reverse phase 

columns and fluorescence detection for quantification. The compounds analyzed are found in Table IV. The method development 

was conducted under a CRC contract* 2 3 ' and a round-robin was 

conducted by the CCP* 2 4 ' . The second method requires only a 

silic a gel cleanup followe d by an HPLC separation . I t i s 

adequate for routine screening of samples but is not as comprehensive as Method No. 1. 

C. DEFINITIONS/ABBREVIATIONS 

CCP - Chemical Characterizatio n Panel, CRC-APRAC CAPI-1-64 

In-House Group 

PAH - Polycyclic aromati c hydrocarbons-fused ring aromatic 

compounds 

N02PAH - Nitrated PAH 

ACN - Acetonitrile 

v/v - Volume/volume 

SOF - Dichloromethane extractable fraction 

TOE - Toluene:ethanol extractable fraction 

VOC - Vapor phase organic compounds 

HPLC - High performance liqui d chromatograph 
P.34 

-40-

PAH Compounds: 

Fl 

Ph 

Anth 

Fluor 

Py 

BaA 

Ch 

BbF 

BkF 

BaP 

B(g,h,i) -

BeP 

Fluorene 

Phenanthrene 

Anthracene 

Fluoranthene 

Pyrene 

Benz(a)Anthracene 

Chrysene 

Benzo(b)Fluoranthene 

Benzo(k)Fluoranthene 

Benz(a)Pyrene 

Benzo(g,h,i)Perylene 

Benz(e)Pyrene 

D. EQUIPMENT 

HPLC - High performance liquid chromatograph. Stop flow capability is preferred but is not required. Various instruments are 

available. 

UV Detector - Wavelength = 254 nm (used for fractionation of 

extract in Method 1). 

Bondapak NH2 Column - Normal phase aminosilane semipreparative 

column, 7.5 mm x 30 cm. 

Vydac 5 Micron Column - Reversed phase analytical column, 4.6 mm 

x 25 cm. 

Fluorescence Detector - Wavelength capability as shown in Tables 

V, VI, and VII. 

Evaporator - Kuderna-Danish evaporator with a Micro-Snyder condensor. 

E. SOLVENTS 

Distilled in Glass or equivalent quality: 

Hexane 

. Isooctane 

Dichloromethane (MeCl2) 

Acetonitrile (ACN) 

Tetrahydrofuran (THF) 

All solvents should be degassed immediately prior to use. 
P.35 

•41-

F. PROCEDURES 

The analysis of PAH compounds in diesel particulate usually 

involves an extraction to remove the organic fraction containing 

the PAH's from the particulate or collection media. The extract 

undergoes a separation procedure to isolate the PAH compounds. 

This is followed by chromatographic analysis of the PAH. The 

large number of compounds in diesel extracts make the precise and 

accurate analysis of the PAH difficul t unless there is prior 

cleanup of the sample. 

Two methods are described in thi s report. Method 1 involves a 

more complicated preparation and analysis of the PAH by ring 

size. The fractions are analyzed by HPLC using specific conditions for each fraction . Considerable time and effort are 

required to analyze PAH by this method but excellent accuracy and 

precision are obtained. 

The second method, Method 2, requires less effort. I t involves 

cleanup of the sample using open column silica gel chromatography 

prior to analysis by reverse phase HPLC. 
P.36 

-43-

METHOD 1 

This method was developed by the CRC*2 3' and evaluated in a roundrobin by the CCP*24'. The method may be further modified as a result 

of a second round-robin currently in progress, but major changes are 

unlikely. A schematic summarizing the method is found in Figure 10. 

This method is applicable to SOF, TOE, and VOC samples. 

Step 1 - Extract Preparation 

• Following the extraction of the SOF, TOE, or VOC, the extracts 

are reduced in volume to about 1 ml by evaporation of the solvent 

using a gentle stream of clean nitrogen in the Kuderna-Danish 

evaporator at 65°C. The solvent level is adjusted, if required, 

to about 1 ml just prior to making a solvent exchange to heptane. 

(Isooctane can be used if extract solubility problems are observed.) In the case of TOE fractions, a solvent exchange to 

dichloromethane must be conducted prior to the heptane exchange. 

• In the heptane exchange add 2 ml of heptane and evaporate the 

sample under a gentle stream of nitrogen to less than 0.5 ml. 

Add an additional 3 ml of heptane and concentrate the sample to a 

final volume of exactly 1 ml. The extract in heptane (50 yl) is 

fractionated using the normal phase Bondapak column. (Note: 

Small extract samples, less than 4 mg, or samples containing low 

PAH concentrations may require further concentrating of the heptane solution to obtain adequate samples from the fractionation 

in the next step. This can better be evaluated after conducting 

Step 2.) 

Step 2 - Extract Fractionation 

• The heptane solution (50 yl) is fractionated using normal phase 

HPLC on the 7.5 mm x 30 cm Bondapak aminosilane column. The 

eluant 1s hexane at a flow rate of 3 ml/min. The eluting compounds are monitored using a UV detector at a wavelength of 254 

nm. Three fractions are collected as they elute from the column 

at approximately 0-11 minutes, 11-21 minutes and 21-40 minutes. 

A typical separation is found in Figure 11. Fraction 1 contains 

PAH with 3 rings or less, Fraction 2 contains 4-ring compounds, 

and Fraction 3 contains the PAH with 5 or more rings. The collection times may vary slightly depending on experimental 

factors, e.g., column differences, sample composition, etc. It 

is important, therefore, to periodically run a PAH standard. The 

actual collection times can be determined by analyzing a standard 

solution containing both Fluor and Chrysene. The collection time 

for Fraction 2 begins just prior to the elution of Fluor and ends 

just after the elution of Chrysene. The NBS standard*25' contains both fluoranthene and chrysene, and can be used to establish actual collection times. 
P.37 

-44-

METHOD 1 - (Continued) 

The flow rates should be checked volumetrically to accurately 

establish the retention volume in the HPLC system from the UV 

detector to the collection point. 

Following the completion of the fractionation of the extract, the 

column should be backflushed. Use a linear gradient to 100% 

dichloromethane at a rate of 10% per minute. This is followed by 

a reverse gradient back to 100% hexane and equilibration of the 

column for 15 minutes at 100% hexane. 

Periodic regeneration of the column may be required if significant changes in the profile or retention times occur. Flushing 

the column for one hour with THF may be required*26,27'. 

Step 3 - Fraction Analysis 

• The three fractions collected are concentrated to 5-8 ml at 

ambient temperature using a gentle stream of clean nitrogen. The 

samples are then transferred to 10 ml concentrator tubes and 

reduced in volume to 2 ml. A volume of 1 ml ACN is added along 

with sufficient dichloromethane to make a miscible solution. The 

solution is reduced in volume to about 0.5 ml under nitrogen. 

ACN is added to Fractions 1 and 2 to bring their volume to 

exactly 2.0 ml. Fraction 3 should be at exactly 0.5 ml. (Note: 

If samples are not used immediately, some readjustment of volumes 

with ACN may be required.) 

t The three fractions are analyzed using single column reverse 

phase HPLC and selective fluorescence detection. The specific 

conditions are described in Tables V, VI, and VII. 

• All three separations of the fractions are performed on the 4.6 

mm x 25 cm Vydac five-micron reverse-phase column using an 

acetonitrile/water gradient. Initial conditions are reestablished 1n each case by using a reverse phase gradient of 5% per 

minute until the initial conditions are attained. The system is 

allowed to reequlHbrate for 15 minutes prior to the injection of 

the next sample. 

Additional details on the method can be found in References 23, 24, 

and 26. 
P.38 

-45-

METHOD 2 

This method was one utilized by two of the participants of the CCP and 

was submitted to the group for consideration in 1980*28'. The method, 

which is summarized in Figure 12, was used in the round-robin and has 

been compared between laboratories. Typical traces are shown on 

Figure 13. Similar procedures have been used by panel members*5'

29'. 

Repeatability within the laboratory is normally around 10% r.s.d. It 

is presented as a convenient method for analyzing large numbers of 

samples and can be automated for routine analysis. The separation of 

certain compounds such as BaA and BeP is not clean but the procedure 

is useful in screening samples. Method 1 is the preferred method when 

precision and accuracy of all 11 compounds are of concern. 

Step 1 - Extract Preparation 

o The extract from the SOF or VOC are transferred to a KhudernaDanish evaporative concentrator flask along with rinsings of the 

flasks. The Kuderna-Danish units along with the Micro-Snyder 

condensor are placed in an aluminum heater block at 40-45°C. The 

samples are blown down to a 1 ml volume with a gentle stream of 

clean, dry nitrogen. (TOE extracts have to undergo a solvent 

exchange to dichloromethane prior to undergoing Step 1.) The 

samples can be stored in 1-ml vials in the freezer until sufficient samples are obtained. (Six samples can be processed 

manually in an eight-hour day, or some two dozen can be run on an 

automatic processer overnite.) 

o The extracts are fractionated by open silica gel column chromatography to remove interferring oxidized material. The silica 

gel columns can be purchased or prepared as follows: A small 

amount of Ottawa (white) sand is placed in the bottom of an open 

1-cm column and 10 cc of chromatographic grade silica gel (60-230 

mesh) added. The gel should be activated overnite at 175°C. The 

column should be lightly tapped to insure a reasonably tight 

column bed and a small amount of Ottawa sand is placed on top of 

the column. The column is rinsed with 25 ml of hexane. If the 

columns are not going to be used immediately, they should be kept 

wet by closing off the stopcock of the chromatographic column as 

the hexane level just reaches the top of the sand layer on top of 

the column. 

o To clean up the extract, each 1-ml sample is placed on its own 

column by pipette transfer and two rinsings of the Kuderna-Danish 

evaporator tube or vial are also added to the column. As the 

extract enters the column, it is followed by 25 ml of hexane and 

then by 25 ml of dichloromethane. ALL eluting liquids are collected in one 100 ml beaker. When the last of the solvents has 

drained, about half of the mixture is poured into the evaporator 

tube and concentrated down to 2-3 ml. The remainder of the 

mixture along with two dichloromethane rinsings of the beaker are 
P.39 

•46-

METHOD 2 - (Continued) 

added and blown down under nitrogen at 40-45°C. I f the original 

extract weight was greater than 4 mg, the samples are blown down 

to a final volume of 1 ml. I f the extract weight was less than 4 

mg, the final volume is 0.5 ml. 

Next, transfer the sample to a 10-ml volumetric flask along with 

two washings of the sample container. Blow down with nitrogen to 

1 ml (>4 mg sample) or 0.2-0.3 ml (<4 mg sample) and bring the 

volume up to 10 ml with acetonitrile. Sample is transferred to a 

10 ml vial and stored in the freezer unti l ready for HPLC 

analysis. 

Step 2 - Sample Analysis 

• A Zorbax ODS column (4.6 mm x 25 cm) is used for the analysis. A 

short (4.6 mm x 5 cm) micro-Porasil C-18 column is used as a 

precolumn to prolong the lif e of the Zorbax column. 

• The NBS PAH standard* 2 1 ' is used to calibrate the system. One 

millilite r of the NBS standard is diluted to 10 mis with acetonitrile . This is further diluted 1:10 with acetonitrile . Ten 

microliter s of thi s solution is injected for the calibration . 

The HPLC operating conditions are: 

Flow = 1.0 ml/min. 

Solvent = ACN/Water. Initia l % ACN = 74% 

Final % ACN = 86% 

Time = 40 minutes 

(Waters 660 programer solvent Curve #7) 

Column = Zorbax ODS, 4.6 mm x 25 cm with C18 

li-Porasil precolumn 

Fluorescence Detector Conditions = Ex/Em 280/389 

• Solvents are degassed for at least one hour at approximately 150 

mm Hg vacuum. The solvents are maintained under a helium blanket 

during use by bubbling helium through the solvents at a slow 

rate. 

• Injection volumes of samples vary depending on the fina l tota l 

volume of sample and the milligrams of extract in the sample. A 

20-ul injection is a good starting point. 

• The solvent program is run in 40 minutes and then the fina l 

condition is held for 20 minutes. This is followed by a rapid 

return to the original conditions and a 10-minute equilibrium 

delay before injectin g the next sample. Total run time from 

injection to injection is 70 minutes. 
P.40 

REFERENCE S 
' * * 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

P.41 

.—— — ' 

-49-

REFERENCES 

Perez, J.M., Lipari , F. and Seizinger, D.E., "Cooperative Development of Analytical Methods for Diesel Emissions and Particulates," SAE Paper No. 840413, Detroit, MI, March 1984. 

Tejada, S., CRC-APRAC CAPI-1-64 Chemical Characterization of 

Diesel Exhaust Emissions Workshop II , Dearborn, MI, March 1985. 

Tejada, S.B., "Evaluation i f Silica Gel Cartridges Coated In Situ 

with Acidified 2,4-Dinitrophenylhydrazine for Sampling Aldehydes 

and Ketones in A1r," Intern. J. Environ., Anal. Chem., Vol. 26, 

pp. 167-185, 1986. 

Perez, J.M., "Chemical Characterization of Diesel Exhaust - A 

Report of Cooperative Studies of Analytical Methods," Preprint 

No. 83-48.5, 76th Annual APCA Meeting, Atlanta, GA, June 1983. 

Wall, J.C. and Hoekman, SX , "Fuel Composition Effects on HeavyDuty Diesel Particulate Emissions," SAE Paper No. 841364, 

Baltimore, MD, October 1984. 

"Methylene Chloride Facing Regulation," Chemical and Engineering 

News, p. 17, March 17, 1986. 

SAE Recommended Practices, Society of Automotive Engineers, 400 

Commonwealth Drive, Warrendale, PA 15096. 

US EPA Heavy-Duty Diesel Transient Test, Code of Federal Regulations, Title 40, Part 86, Subpart N. 

Lipkea, W.H., Johnson, J.H., and Vuk, C.T., "The Physical and 

Chemical Character of Diesel Particulate Emissions - Measurement 

Techniques and Fundamental Considerations," SAE Paper No. 78018 

(SP-430), 1978. 

10. MacDonald, J.S., Plee, S.L., D'Arcy, J.B., and Schrek, R.M., 

"Experimental Measurements of the Independent Effects of Dilution 

Ratio and Filte r Temperature on Diesel Exhaust Particulate 

Samples," SAE Paper No. 800185, Detroit, MI, February 1980. 

11. Elsenberg, W.J., "Development of a Method for the Analysis of 

Polycyclic Aromatic Hydrocarbons in Diesel Exhaust Emissions," 

Final Report by I IT Research Institut e to the Coordinating 

Research Council, Inc., Atlanta, GA, October 1983. 

12. Williams, R.L., Perez, J.M., and Griffing , M.E., "A Review of 

Sampling Condition Effects on Polynuclear Aromatic Hydrocarbons 

(PNA) from Heavy-Duty Diesel Engines," SAE Paper No. 852081, 

Tulsa, OK, October 1985. 
P.42 

-50-

REFERENCES - (Continued) 

13. 

14. 

15. 

16. 

17. 

18. 

19. 

20. 

21. 

22. 

23. 

Coordinating Research Council, Inc., "Informational Report on the 

Measurement of Diesel Particulate Emissions," CRC Report No. 522, 

June 1982. 

MacDonald, J.S., Barsic, N.J., Gross, G.P., Shahed, S.M., and 

Johnson, J.H., "Status of Diesel Particulat e Measurement 

Methods," SAE Paper No. 840345, Detroit, MI, March 1984. 

Seizinger, D.E., Private Communication to the Chemical Characterization Panel of the CRC-APRAC Program Group on Composition of 

Diesel Exhaust, 1981. 

Shimpi, S.A. and Yu, M., "Determination of a Reliable and Effi -

cient Diesel Particulate Hydrocarbon Extraction Process," SAE 

Paper No. 811183, Tulsa, OK, October 1981. 

DI0NEXR Models 10/14 Ion Chromatograph Operation and Maintenance 

Manuel, DIONEX Corporation, Sunnyvale, CA, January 1979. 

Schuetzle, D. and Perez, J.M., "A CRC Cooperative Comparison of 

Extraction and HPLC Techniques for Diesel Particulate Emissions," 

Preprint No. 81-56.4, 74th Annual APCA Meeting, Philadelphia, PA, 

June 1982. 

Hare, C.T., "Supplemental Study of Fuel Property and Injection 

and Combustion System Type Effects on Emissions from Light-Duty 

Diesels," Final Report by Southwest Research Institut e to CRCAPRAC CAPE-32-80 Project Group, Coordinating Research Council, 

Inc., Atlanta, GA, November 1985. 

Standard Materials, SRM #1650, National Bureau of Standards, 

Washington, D. C. 

Tejada, S.B., Zweidinger, R.B., and Sigsby, J.E., Jr., "Fluorescence Detector and Identification of N1tro-Derivat1ves of Polynuclear Aromatic Hydrocarbons by On-Column Catalytic Reduction to 

Aromatic Amines," Anal. Chem., pp. 1827-1834, July 1986. 

Menzies, K.T., et al , "Development of a Routine Technique for 

Analysis of a N1tro-PAH 1n Diesel Particulate Extract," Final 

Report by A. D. Little , Inc. to CRC-APRAC CAPE-30-81 Project 

Group, Coordinating Research Council, Inc., Atlanta, Georgia, 

February 1985. 

Elsenberg, W.C, "Development of a Method for the Analysis of 

Polycyclic Aromatic Hydrocarbons in Diesel Exhaust Emissions," 

Final Report by IIT Research Institut e to CRC-APRAC CAPE-30-81 

Project Group, Coordinating Research Council, Inc., Atlanta, GA, 

October 1983. 
P.43 

-51 -

REFERENCES - (Continued) 

24. Eisenberg, W.C, Schuetzle, D., and Williams, R.L., "Cooperative 

Evaluation of Methods for the Analysis of PAH in Extracts from 

Diesel Particulate Emissions," SAE Paper No. 840414, Detroit, MI, 

March 1984. 

25. Standard Materials, Priority Pollutant PAH, SRM #1647, National 

Bureau of Standards, Washington, D. C. 

26. Eisenberg, W.C and Cunningham, D.L.B., "Analysis of PAH in 

Diesel Emissions Using HPLC: A Method Development Study," 

Presented at the Eighth International Symposium on Polynuclear 

Aromatic Hydrocarbons, Columbus, OH, October 1983. 

27. Warner, I., Karlesky, D., and Skelly, D.C, "Reactivation of an 

Amino Bonded Phase Liquid Chromatographic Column," Anal. Chem., 

53:2146, 1981. 

28. Coordinating Research Council, Inc., "Informational Report on the 

Measurement and Characterization of Diesel Exhaust Emissions," 

CRC Report No. 517, December 1980. 

29. Swarin, S.J. and Williams, R.L., "Polynuclear Aromatic Hydrocarbons: Chemistry and Biological Effects," Bjorseth, A. and 

Dennis, A.J., editors, Battelle Press, Columbus, Ohio, 1980. 
P.44 

TABLE S 

AND 

FIGURE S 
Aldehyde or Ketone 

Formaldehyde 

Acetaldehyde 

Acetone 

Propionaldehyde 

Acrolein 

n-Butyraldehyde 

Isobutyraldehyde 

Methyl ethyl ketone 

Crotonaldehyde 

n-Valeraldehyde 

Iso-Valeraldehyde 

Caproaldehyde 

Enanthaldehyde 

Benzaldehyde 

p-Tolualdehyde 

IUC Name 

Methanal 

Ethanal 

2-Propanone 

Propanal 

Propenal 

Butanal 

2-Methylpropanal 

2-Butanone 

trans-2-Butenal 

Pentanal 

3-Methylbutanal 

Hexanal 

Heptanal 

Benzenecarbonal 

4-Methy1benzenecarbonal 

TABLE I 

PHYSICAL PROPERTIES OF CARBONYL COMPOUNDS 

Chemical Molecular 

Formula Weight 

CH20 30.03 

CH3CH0 44.05 

CH3COCH3 58.08 

CH3CH2CH0 58.08 

CH2:CHCH0 56.07 

CH3(CH2)2CH0 72.10 

CH3CH(CH3)CH0 72.11 

CH3C0CH2CH3 72.11 

CH3CH:CHCH0 70.09 

CH3(CH)3CH0 86.13 

(CH3)2CHCH2CH0 86.13 

CH3(CH2)4CH0 100.16 

CH3(CH2)5CH0 114.18 

C6H5CH0 106.13 

CH3C6H4CH0 120.14 

Melting 

Pt., °C 

-92 

-121 

-95 

-81 

-87.7 

-99 

-65.9 

-84 

-74 

-92 

-51 

-56 

-45 

-26 

Mol. Wt. 

210.15 

224.1b 

238.21 

238.21 

236.20 

252.23 

252.23 

252.23 

250.21 

266.26 

266.26 

279.28 

294.31 

286.25 

300.27 

DNPH Derivative 

Melting 

Pt. , °C 

167 

167 

128 

156 

165 

122 

182 

— 

190 

106 

— 

104 

--

237 

194 

Density 

0.815 

0.783 

0.792 

0.807 

0.841 

0.817 

0.794 

0.805 

0.858 

0.820 

0.805 

0.833 

0.850 

1.05 

1.02 

• • 

Rel Ret 

Time 

0.453 

0.574 

0.714 

0.795 

0.699 , 

tn tn 

1 

0.911 

— 

0.870 

— 

--

1.23 

— 

1.00 
TABLE II 

STORAGE STABILITY 

(ng/yL) 

SAMPLE NO. 

Formaldehyde 

Acetaldehyde 

Acrolein 

Acetone 

Propionald. 

Crotonald. 

Isobutryald. 

Benzald. 

Hexanal 

ORIG. 

23.0 

3.98 

1.03 

0.85 

0.86 

0.52 

0.58 

0.31 

0.19 

1 

A 

22.0 

3.82 

0.16 

0.83 

0.82 

0.42 

0.58 

0.29 

0.14 

A = 

B 

22.7 

3.97 

0.21 

0.89 

0.84 

0.47 

0.58 

0.31 

0.10 

6 weeks 

ORIG. 

23.6 

4.16 

0.94 

0.90 

0.91 

0.52 

0.61 

0.32 

0.15 

B = 

2 

A 

22.0 

3.86 

0.17 

0.89 

0.83 

0.32 

0.85 

0.27 

0.12 

2 months 

B 

22.3 

3.81 

0.20 

0.87 

0.84 

0.30 

0.74 

0.30 

0.10 

ORIG. 

14.1 

2.30 

0.77 

0.56 

0.47 

0.42 

0.34 

0.09 

0.07 

ND = Not 

3 

A 

13.5 

2.08 

0.11 

0.56 

0.43 

0.14 

0.42 

ND 

ND 

Detected 

B 

13.8 

2.06 

0.14 

0.57 

0.47 

0.12 

0.35 

ND 

ND 

ORIG. 

14.1 

2.24 

0.67 

0.54 

0.47 

0.30 

0.32 

ND 

ND 

4 

A 

13.3 

2.01 

0.12 

0.53 

0.44 

0.14 

0.33 

ND 

ND 

B 

13.5 

1.96 

0.09 

0.52 

0.45 

0.12 

0.42 

ND 

ND 

I 

cn 

i 
-57-

TABLE III 

COMPARISON OF SOF AND VACUUM REMOVAL OF ORGANIC FRACTION 

Sample 

Size, mg 

9.90 

10.2 

7.77 

7.77 

SOF, 

W t. % 

36.4 

43.4 

46.1 

Vacuum Temperatu 

200°F 275°F 

re* 

350°F 

Wt. Loss, % 

38.6 

22.0 

48.6 

41.4 

48.2 

39.5 

44.0 

49.2 

51.0 

* All samples were under 15" vacuum (A15" Hg) for 6 hours. 
-58-

P.48 

TABLE IV 

ELUTION OF POLYCYCLIC AROMATIC HYDROCARBONS 

PAH 

Fluorene 

Anthracene 

Phenanthracene 

Fluoranthene 

Pyrene 

Benz[a]anthracene 

Chrysene 

Benzo[k]fluoranthene 

Benz[a]pyrene 

Benzo[b]fluoranthene 

Benzo[g,h,i]perylene 

ON A BONDAPAK NH2 

Elution 

Time, min. 

6.87 

9.36 

9.72 

12.45 

12.27 

17.61 

17.85 

21.45 

22.41 

23.04 

31.26 

COLUMN 

Relative 

Elution 

Time, min. 

0.55 

0.75 

0.78 

1.00 

0.98 

1.41 

1.43 

1.70 

1.80 

1.85 

2.51 

Fraction 

Collection 

Times 

Fraction 1 

0-11 min. 

Fraction 2 

11-21 min 

Fraction 3 

21-40 min 
P.49 

•59-

TABLE V 

HIGH PERFORMANCE LIQUID CHROMATOGRAPHY 

OF POLYCYCLIC AROMATIC HYDROCARBONS: FRACTION l 1 

PAH 

Fluorene 

Phenanthrene 

Anthracene 

Retention 

Time, min. 

16.50 

18.85 

20.92 

Fluorescence 

Wavelength, nm 

Excitation 

260 

260 

260 

Emission0 

370 

370 

370 

Detection 

Limit, nqz 

3.67 

0.93 

0.50 

1. HPLC elution conditions: 4.6 mm x 25.0 cm Vydac 5 micron 

reverse-phase column; linear gradient, acetonitrile/water (50/50, 

V/V) to acetonitrile/water (70/30, V/V) in 30 min. then to 100% 

acetonitril e in 10 min., followed by 10 min. at 100% acetonitrile . The system was returned to initia l conditions using a 

reverse gradient of 5%/min. for 10 min. and equilibrated at 

initia l conditions for 15 min.; flow: 1.0 ml/min., detector 

range: 1.0 (minimum range: 0.01); injection volume: 15 yl. 

2. The detection limi t was defined as the on-column amount of 

compound that would give a peak that was 5 times the baseline 

noise under these instrumental conditions. 

3. A detector with a 370 nm emission cut-off filte r was used. 
P.50 

-60-

TABLE VI 

HIGH PERFORMANCE LIQUID CHROMATOGRAPHY 

OF POLYCYCLIC AROMATIC HYDROCARBONS: FRACTION 2 1 

PAH 

Fluoranthene 

Pyrene 

Benz[a]anthracene 

Chrysene 

Retention 

Time, min. 

10.50 

11.97 

17.40 

18.72 

Fluorescence 

Wavelength, nm 

Excitation 

260 

260 

280 

260 

Emission0 

370 

370 

389 

370 

Detection 

Limit, ng 

1.22 

2.26 

0.51 

0.59 

2. 

3. 

HPLC elution conditions: 4.6 mm x 25.0 cm Vydac 5 micron 

reverse-phase column; isocrati c elution , acetonitrile/water 

(70/30, V/V) for 15 min., then a linear gradient to 100% acetonitril e in 15 min., followed by 15 min. at 100% acetonitrile. The 

system was returned to initia l conditions using a 10 min. 

gradient followed by an equilibration period of 15 min.; flow: 

1.0 ml/min.; detector range: 1.0 (minimum range: 0.01); injection volume: 30 yl. 

The detection limi t was defined as the on-column amount of 

compound that would give a peak that was 5 times the baseline 

noise under these instrumental conditions. 

A detector with a 370 and 389 nm emission cut-off filte r was used 

in these analyses. 
P.51 

•61-

TABLE VII 

HIGH PERFORMANCE LIQUID CHROMATOGRAPHY 

OF POLYCYCLIC AROMATIC HYDROCARBONS: FRACTION 31 

Fluorescence 

Retention Wavelength, nm Detection, 

PAH 

Benzo[b]fluoranthene 

Benzo[k]fluoranthene 

Benzo[a]pyrene 

Benzo[g,h,i]perylene 

Time, min. 

32.34 

34.11 

35.73 

40.82 

Excitation 

280 

280 

280 

280 

Emission0 

389 

389 

389 

389 

Limit, ng 

0.29 

0.23 

0.29 

1.71 

1. HPLC elution conditions: 4.6 mm x 25.0 cm Vydac 5 micron 

reverse-phase column; linear gradient, acetonitrile/water (50/50, 

V/V) to acetonitril e in 40 min., followed by 20 min. at 100% 

acetonitrile. The system was returned to initia l conditions for 

15 min.; flow: 1.0 ml/min.; detector range: 1.0 (minimum range: 

0.01); injection volume: 30 yl. 

2. The detection limi t was defined as the on-column amount of 

compound that would give a peak that was 5 times the baseline 

noise under these instrumental conditions. 

3. A detector with a 389 nm emission cut-off filte r was used. 
P.52 

-62-

FIGURE 1 

SAMPLING CART 

(SCHEMATIC DIAGRAM) 

FILTERS 

(AS REQUIRED) 

.SOLENOID 

ON-OFF 

IMPINGERS 

DRYING* 

TUBE 

FLOWMETER 

PUMP 

DRY-GAS 

METER 

TEMP READO 

ThlTlftl i T "*" VOLUME 

EMERGENCY POWER 
P.53 

-63-

FIGURE 2 

CARBONYL ANALYSIS METHOD 

PREPARATION' 

SAMPLING 

HPLC ANALYSIS" 

TIME (MIN) 

START 

0 

a 

9 

15 

20 

00 

STOP 

8 

9 

15 

20 

30 

35 

I 

FLOW RATE 

(ML/MIN) 

0.7 

1.0 

1.0 

1.0 

1.0 

10 

SOLVENT — 

GRAOIENT CONC 

(VOL %) 

67ACN/33 H,0 

67ACN/33 H,0 

GRAOIENT TO 85 ACN 

GRAOIENT TO 100 ACN 

100 ACN 

REVERSE GRAOIENT 

TO 67 ACN/23 H,0 

•ONPH SOLUTIONS 

STANOAROS 

"HPLC — 4.8 mm x 25 cm column — 

5M Zortax OOS; 600 PSI (initial); 

UV-365 ntrr, sensitivity 02 AUFS 
FIGURE 3 

CHROMOTOGRAM OF THE 

STANDARD DNPH-ALDEHYDE MIXTURE 

Relative Absorbance 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

11. 

12. 

13. 

14. 

15. 

DNPH 

Formaldehyde 

Acetaldehyde 

Acrolein 

Acetone 

Propionaldehyde 

Crotonaldehyde 

Iso-butyraldehyde 

Benzaldehyde 

Iso-valeral dehyde 

Valeral dehyde 

p-Tolualdehyde 

Hexal dehyde 

Heptaldehyde 

Octal dehyde i 

cn 

-P. 

i 

10 12 14 

Time (min) 

fe 
FIGURE 4 

250 FORMALDEHYDE STABILITY 

200 

j_ 

Q. 

E 

CO 

co 

UJ 150 

Q 

SAMPLE 

1 

I 

UJ 

cn 

i 

CC 

O 

100 • - - » 

50 

16 24 

HOURS 

32 40 48 
100 r FIGURE 5 

ACROLEIN STABILITY 

SAMPLE 

1 

i 

CTt 

I 

16 24 32 40 

ELAPSED TIME - HOURS 

48 
500 

FIGURE 6 

TOTAL ALDEHYDE STABILITY 

Engine Operation 

Condition 

No. 1 

-22 400 

Q. 

E 

at 

co 

UJ 

5 300 

I 

UJ 

a 

i 

o-> 

I 

P 200 

NO. 2 

100 

16 

ELAPSED TIME 

24 

HOURS 

32 40 
P.58 

-68-

FIGURE 7 - SOXHLET 
P.59 

-69-

FIGURE 8 

MASS OF BOUND H20 PER GRAM H2S04 

IN AN AQUEOUS SOLUTION VERSUS RELATIVE HUMIDITY (25°C) 

o 

cn 

CM 

o 

CM 

X 

20 40 60 80 100 

Relative Humidity, % 
P.60 

-70-

FIGURE 9 

SCHEMATIC OF NITROPYRENE ANALYSIS SYSTEM 

Solvent 

Reservoir 

771 Methanol 

232 Water 

T Flow 

1.1 tni/min 

I 

(Pump ] (Pump j 

J «|l M 

Solvent 

Reservoir 

1002 Methanol 

Reduction Catalyst 

3 Inch x 4.6 mm 

packed with groundup 3-way catalyst , 

70 mesh 

For removal of oxygen 

i Septum-less 

Inj eccor 

Analytica l Column 

Zorbax ODS Column 

25 cm * 4.6 ram 

I Reduction Catalyst 

3 inch * 4.6 ~a 

—fJ packed with ground-up 

3-way catalyst , 70 mesh 

Analytica l Column 

Zorbax ODS Column 

15 cm x 4.6 mm 

Waste 

Fluorescence Detector 

360 nm excitatio n 

430 nm emission for 

1-nitropyrene 
P.61 

:

 AJ * -71-

FIGURE 10 

HPLC PAH METHOD NO. 1 

FRACTION 1 

(3 OR LESS RINGS) 

DIESEL PARTICULATE 

EXTRACTION 

KUDERNA-DANISH 

(SOLVENT EXCHANGE) 

EXTRACT FRACTIONATION 

(BONDAPAK NHo) l2] * 

FRACTION 2 

(4 RINGS) 

SOLVENT EXCHANGE AND 

SAMPLE CONCENTRATION 

FRACTION 3 

(5 OR MORE RINGS) 

VYDAC 5 ym COLUMN SEPARATION 

SEE TABLE V SEE TABLE VI SEE TABLE VII 

See Figure 11. 
FIGURE 11 

HPLC METHOD SUMMARY - FRACTIONATION OF THE DIESEL EXTRACT 

STEP1 

FRACTION -

i 

i 

STEP 2 VYDAC 5 COLUMN — FLUORESCENCE DETECTION 

FRACTION I FLUORENE 

ANTRACENE 

PHENANTHENE 

FRACTION II FLUORANTHENE 

PYRENE 

BENZ(A)ANTHRACENE 

CHRYSENE 

FRACTION III BENZO(B)FLUORANTHENE 

BENZO(K)FLUORANTHENE 

BENZO(A)PYRENE 

BENZO(GHI)PERYLENE 

SEPARATION CHECKED 

USING NBS SRM #1647 

(16 PAH STANDARDS) 

-». , 
V 

1 —J 

A « • «* 

« u # 

-73-

FIGURE 12 

HPLC PAH METHOD NO. 2 

DIESEL PARTICULATE 

EXTRACTION - MECL2 

SILICA GEL SEPARATION 

HEXANE/MECL2 

SAMPLE CONCENTRATED 

TO 1-ml (KUDERNA-DANISH 

SOLVENT EXCHANGE (ACN) 

HPLC-FLUORESCENCE 

EX/EM = 280/389 

ZORBAX ODS 

P.63 

) 
-74-

FIGURE 13 

TYPICAL HPLC TRACES - METHOD 2 

A. PAH STANDARD SOL'N 

T-mr 

3. MESCL ENCINE 

^ARTICULATE 

EXTRACT isory 

&-" .*vK~~. 

W