NISTIR 6647

Properties of a 50/50 Mixture 

of Jet-A + S-8

Thomas J. Bruno

Arno Laesecke

Stephanie L. Outcalt

Hans-Dieter Seelig

Beverly L. Smith

NISTIR 6647

Properties of a 50/50 Mixture 

of Jet-A + S-8 

Thomas J. Bruno 

Arno Laesecke 

Stephanie L. Outcalt 

Hans-Dieter Seelig 

Beverly L. Smith 

Thermophysical Properties Division

325 Broadway

Boulder, CO 80305

March 2007 

U.S. Department of Commerce 

Carlos M. Gutierrez, Secretary 

Technology Administration 

Robert Cresanti, Under Secretary for Technology 

National Institute of Standards and Technology 

William Jeffrey, Director 
Executive Summary 

• Report of the chemical analyses of Jet-A and S-8 (samples received from AFRL). 

• Report of the distillation curves of 50/50, 25/75 and 75/25 Jet-A + S-8. 

• Report of density survey measurements of 50/50 Jet-A + S-8. 

• Report of viscosity survey measurements of 50/50 Jet-A + S-8. 

• Report of speed of sound survey measurements of 50/50 Jet-A + S-8. 

• Report of compressed liquid density measurements of 50/50 Jet-A + S-8. 

ii
Contents 

1. Introduction.....................................................................................................................1 

2. Chemical Analysis of Jet-A and S-8...............................................................................2 

3. Distillation Curves of Jet-A + S-8 ..................................................................................6 

4. Density (at Atmospheric Pressure) for 50/50 Jet-A + S-8 ............................................14 

5. Viscosity (at Atmospheric Pressure) for 50/50 Jet-A + S-8 .........................................19 

6. Speed of Sound Measurement (at Atmospheric Pressure) for 50/50 Jet-A + S-8 ........23 

7. Correlations for the Density, Viscosity, and Speed of Sound of 50/50 Jet-A + S-8.....27 

8. Compressed Liquid Density Measurements for 50/50 Jet-A + S-8 ..............................28 

9. References.....................................................................................................................31 

iii

Properties of a 50/50 Mixture of Jet-A + S-8*

Thomas J. Bruno, Arno Laesecke, Stephanie L. Outcalt 

Hans-Dieter Seelig, and Beverly L. Smith 

National Institute of Standards and Technology 

325 Broadway 

Boulder, Colorado 80305 

This report describes measurement efforts performed on mixture(s) of aviation 

fuels: Jet-A + S-8. The primary mixture is a 50/50 (vol/vol) combination of the 

two fuels. Measurements include chemical analysis, density, viscosity, speed of 

sound and vapor pressure (by a distillation curve measurement). This document 

compiles in one source the available measured data for the mixture. 

Keywords: density; distillation curve; speed of sound; thermal conductivity; 

vapor pressure; viscosity 

1. Introduction 

The major gas turbine fuel that is currently the most common fuel used by the United States 

military is JP-8 (MIL-DTL-83133), a kerosene fraction that has a higher flash point than the 

main military predecessor, JP-4 [1]. JP-8 was first introduced at NATO bases in 1978, hence it 

was also called NATO F-34, and is currently the U.S. Air Force's primary fuel, and the primary 

fuel for U.S. Navy shore-based aviation. Aboard aircraft carriers, the major fuel is JP-5, which 

has an even higher flash point (desirable for safety considerations), although its higher cost 

restricts its use to the specialized fire control needs of aircraft carriers. JP-8 is very similar to Jet 

A-1, the most common commercial gas turbine fuel, with the major differences being in the 

additive package. JP-8 contains an icing inhibitor, corrosion/lubricity enhancer and anti-static 

additive. Jet-A (U.S. domestic commercial jet fuel) differs from Jet-A1 (non-U.S. commercial jet 

fuel) primarily in freezing point (−40 °C as opposed to −47 °C, respectively). The understanding 

of the properties of JP-8 must necessarily begin with understanding the properties of Jet-A, since 

the fluids are very similar and because the additive package is often varied to suit applications, 

climatic regions, and supply streams. 

Environmental concerns, and the potential of disruptions in supply, have led to the development 

of new aviation fuels based on the Fischer Tropsch process. One such fuel made from natural gas 

is designated as S-8 (the “S” referring to synthetic; CAS No. 437986-20-4) [2]. This fluid, which 

is intended as a synthetic JP-8, is a hydrocarbon mixture rich in C7 to C18 linear and branched 

 

*

 Note: In order to describe materials and experimental procedures adequately, it is occasionally necessary to 

identify commercial products by manufacturers’ names or labels. In no instance does such identification imply 

endorsement by the National Institute of Standards and Technology, nor does it imply that the particular product or 

equipment is necessarily the best available for the purpose. 

1
akanes. It has a flash point range between 37.8 °C and 51.8 °C, an auto ignition temperature of 

210 °C, and explosive limits in air between 0.7 and 5 (vol/vol). It is clear in appearance (no dye 

is added to current formulations) and somewhat lower in density, viscosity, and speed of sound 

transmission than typical formulations of Jet-A and JP-8. It is likely that initial applications of S8 will be in formulations mixed with either JP-8 or Jet-A. In view of the comments above on the 

differences between Jet-A and JP-8, the AFRL desired measured properties of a 50/50 (vol/vol) 

mixture of Jet-A and S-8 to guide formulations of test fuel mixtures. This document summarizes 

the measurements done at NIST on this mixture. 

The samples of Jet-A and S-8 were obtained from AFRL. The sample of Jet-A was designated 

POSF-4658, and was a composite sample that was prepared by AFRL from several samples from 

several manufacturers. The S-8 was designated POSF-4734. The 50/50 (vol/vol) mixtures were 

prepared volumetrically at ambient temperature (approximately 23 °C) and atmospheric pressure 

(approximately 83.2 kPa) by use of mixing cylinders. The uncertainty in the volume during the 

preparation of mixtures was 0.1 mL. For the remainder of this report, we will commonly refer to 

the resulting mixture as Jet-A + S-8, or simply as “the mixture.” 

2. Chemical Analyses of Jet-A and S-8

A sample of Jet-A, designated as POSF-4658, was presented for analysis. This sample is a 

composite made from a number of individual lots of Jet-A. The sample was drawn with a 

disposable pipette from a half-gallon steel pail supplied by AFRL. The sample had a very pale 

yellow cast, and did not appear to have any dying agent. The sample appeared to have a viscosity 

and odor typical of kerosenes. 

The sample was analyzed with a gas chromatography−mass spectrometry method. A 30 m 

capillary column with a 0.1 μm coating of 5 % phenyl polydimethyl siloxane was chosen as the 

stationary phase [3]. This phase provides separations based upon boiling temperature and also 

the polarity of the solute. In this context, polarity also includes points of unsaturation or 

aromaticity on the solute molecule. Sample was injected via syringe into a split/splitless injector 

set with a 100 to 1 split ratio. The injector was operated at a temperature of 350 °C and a 

constant head pressure of 8 psig. The sample residence time in the injector was very short; thus 

the effect of sample exposure to this high temperature is expected to be minimal. The column 

was temperature programmed to provide complete and rapid elution with minimal loss of peak 

shape. Initially, the temperature was maintained isothermally at 60 °C for 2 min, followed by a 

2 °C/min ramp to 90 °C, followed by a 10 °C/min ramp to 250 °C. Although the analysis was 

allowed to run for 40 min, all peaks were eluted after approximately 27 min. Mass spectra were 

collected for each peak from 15 to 550 RMM units [4]. Integration of the areas under each peak 

was done with a commercial algorithm optimized to identify peaks that were at least an order of 

magnitude larger than the noise level. 

Before any analysis was done, the mass spectrometer was tuned with a sample of perfluorotributyl amine [3]. Then, after the tune settings were optimized, a blank run was done to ensure 

the absence of extraneous or ghost components, and to determine stationary phase background. 

2
Table 1. The analysis of Jet-A by gas chromatography–mass spectrometry. 

Peak 

no. 

Retention 

time, min 

Peak 

profile 

Correlation 

coefficient 

Confidence Name CAS No. Area 

percentage 

A 1.726 S 72.9 H n-heptane 142-82-5 0.125 

B 1.878 S 76.9 H methyl cyclohexane 108-87-2 0.198 

C 2.084 S 71.6 H 2-methyl heptane 592-27-8 0.202 

1 2.144 S 29.2 H toluene 108-88-3 0.320 

D 2.223 S 41.9 H cis-1,3-dimethyl cyclohexane 638-04-0 0.161 

2 2.351 S 44.0 H n-octane 111-65-9 0.386 

E 2.945 S 31.1 H 1,2,4-trimethyl cyclohexane 2234-75-5 0.189 

3 3.036 S 12.4 H 4-methyl octane 2216-34-4 0.318 

4 3.169 S 37.6 H 1,2-dimethyl benzene 95-47-6 0.575 

5 3.527 S 33.9 H n-nonane 111-84-2 1.030 

6 3.921 S NA U ? 0.321 

7 4.066 S & A NA H x-methyl nonane NA 0.597 

8 4.576 S & A 7.97 Ma 4-methyl nonane 17301-94-9 0.754 

9 4.655 S 35.8 H 1-ethyl-3-methyl benzene 620-14-4 1.296 

10 4.764 S 10.7 H 2,6-dimethyl octane 2051-30-1 0.749 

11 4.836 A 5.27 Ub 1-methyl-3-(2-methylpropyl) 

cyclopentane 

29053-04-1 0.285 

12 5.012 S 27.8 Mb 1-ethyl-4-methyl benzene 622-96-8 0.359 

13 5.049 A 13.7 Mb 1-methyl-2-propyl cyclohexane 4291-79-6 0.370 

14 5.291 S 26.3 H 1,2,4-trimethyl benzene 95-63-6 1.115 

15 5.325 S 37.7 H n-decane 124-18-5 1.67 

16 5.637 S 36 H 1-methyl-2-propyl benzene 1074-17-5 0.367 

17 5.825 S 36 H 4-methyl decane 2847-72-5 0.657 

18 5.910 S 26.9 H 1,3,5-trimethyl benzene 108-67-8 0.949 

19 6.073 S & A NA M x-methyl decane NA 0.613 

20 6.176 S 5.01 Mb 2,3-dimethyl decane 17312-44-6 0.681 

21 6.364 S & A 25.7 Mb 1-ethyl-2,2,6-trimethyl 

cyclohexane 

71186-27-1 0.364 

22 6.516 S & A 35.6 H 1-methyl-3-propyl benzene 1074-43-7 0.569 

F 6.662 S & A NA Ub aromatic NA 0.625 

23 6.589 S 20.4 Mc 5-methyl decane 13151-35-4 0.795 

24 6.728 S 22.9 H 2-methyl decane 6975-98-0 0.686 

25 6.862 A 23.2 H 3-methyl decane 13151-34-3 0.969 

26 7.110 S NA U Aromatic NA 0.540 

27 7.159 S NA U Aromatic NA 0.599 

28 7.310 S 17.9 M 1-methyl-(4-methylethyl) benzene 99-87-6 0.650 

29 7.626 A 22.0 H n-undecane 1120-21-4 2.560 

29 7.971 A NA M x-methyl undecane NA 1.086 

30 8.875 A 22.3 M 1-ethyl-2,3-dimethyl benzene 933-98-2 1.694 

31 9.948 A 19.6 H n-dodecane 112-40-3 3.336 

32 10.324 S 19.0 H 2,6-dimethyl undecane 17301-23-4 1.257 

33 12.377 S & A 10.8 H n-tridecane 629-50-5 3.998 

33a 12.901 S 24.1 M 1,2,3,4-tetrahydro-2,7-dimethyl 

naphthalene 

13065-07-1 0.850 

33b 13.707 S 3.5 M 2,3-dimethyl dodecane 6117-98-2 0.657 

33c 14.138 S 14.5 M 2,6,10-trimethyl dodecane 3891-98-3 0.821 

33d 13.834 S NA M x-methyl tridecane NA 0.919 

33e 13.998 S NA M x-methyl tridecane NA 0.756 

34 14.663 S 29.8 H n-tetradecane 629-59-4 1.905 

35 16.86 S 24.7 H n-pentadecane 629-62-9 1.345 a

 Trailing impurity 

b

 Highly impure composite peak 

c

 There is evidence of an aromatic impurity in this peak, coeluting 

3
The results of the analysis are provided in Table 1. The numbered peaks are the largest peak 

areas recorded on the total ion chromatogram (1 % or higher). Note that these areas are raw areas 

and have not been calibrated with a standard. Lettered peaks are for components between 0.7 and 

1 %, provided the chromatography is good. Double lettered peaks are very early eluting 

components that were included to provide a suite of light components for potential future model 

development. These peaks were chosen in part for their elution order and chromatographic 

purity. 

A sample of S-8, designated POSF 4734, was presented for analysis. The sample was drawn with 

a disposable pipette from a half-gallon steel pail supplied by the AFRL. Approximately 0.5 mL 

of the fluid was drawn and stored in a tightly capped scintillation vial until used. The liquid 

sample was clear, and appeared to have a viscosity lower than that of a typical kerosene. The 

liquid had little discernable odor. The same method used for Jet-A was applied for the analysis of 

S-8. The results of this analysis are provided in Table 2. 

A number of clear differences may be seen in the chemical analyses. First, the sample of Jet-A 

has a typical kerosene composition in that a number of aromatic constituents can be observed. 

No aromatic constituents are listed in Table 2 for S-8. Indeed, no aromatics were detected in S-8 

in any of the analyses that were performed. A second striking feature is the large number of 

linear or simple branched alkanes that are present in S-8, in contrast to the more complex 

constituents found in Jet-A. This is not surprising considering that the feed stock of S-8 is a 

paraffinic wax derived by the Fischer-Tropsch process from natural gas. This paraffinic wax is 

cracked and extensively isomerized to obtain the S-8 jet fuel. 

The samples of Jet-A and S-8 were further examined for hydrocarbon types by use of a mass 

spectrometric classification method summarized in ASTM Method D-2789 [5]. In this method, 

one uses mass spectrometry (or gas chromatography–mass spectrometry) to characterize 

hydrocarbon samples into six types. The six types or families are paraffins, monocycloparaffins, 

dicycloparaffins, alkylbenzenes (or aromatics), indanes and tetralins (grouped as one 

classification), and naphthalenes. Although the method is specified only for application to low 

olefinic gasolines, it is of practical relevance to many complex fluid analyses, and is often 

applied to gas turbine fuels, rocket propellants, and missile fuels. The uncertainty of this method, 

and the potential pitfalls, are discussed elsewhere. For the hydrocarbon type analysis of the 

distillate fraction samples, 1 μL samples were injected into the GC-MS. Because of this 

consistent injection volume, no corrections were needed for sample volume. The results of these 

analyses are provided in Table 3. 

4
Table 2. Detailed analysis for S-8, POSF 4734, provided by AFRL. The peak lettering and 

numbering scheme are described in the text. 

Peak 

no. 

Retention 

time, min 

Peak 

profile 

Correlation 

coefficient 

Confidence Name CAS No. Area 

percentage

aa 2.119 S 72.2 H 2-methyl heptane 592-27-8 0.32 

bb 2.162 A 41.4 H 3-methyl heptane 589-81-1 0.43 

a 2.310 A 26.3 H 1,2,3-trimethyl cyclopentane 15890-40-1 0.96 

1 2.564 A 44.2 H 2,5-dimethyl heptane 2216-30-0 1.13 

2 2.803 A 33.9 H 4-methyl octane 2216-34-4 2.506 

3 2.869 A 16.9 H 3-methyl octane 2216-33-3 1.323 

4 3.123 A 21.6 H n-nonane 111-84-2 1.623 

5 3.358 A 18.5 M 3,5-dimethyl octane 15869-96-9 1.035 

b 3.456 A 29.0 H 2,6-dimethyl octane 2051-30-1 0.756 

6 3.682 A 54.4 H 4-ethyl octane 15869-86-0 1.032 

7 3.757 A 39.8 H 4-methyl nonane 17301-94-9 1.904 

8 3.792 S 39.2 H 2-methyl nonane 871-83-0 1.019 

9 3.866 A 26.9 H 3-methyl nonane 5911-04-6 1.385 

10 4.186 A 51.4 H n-decane 124-18-5 2.050 

11 4.390 A 16.7 M 2-5-dimethyl nonane 17302-27-1 1.175 

12 4.750 S 12.0 M 5-ethyl-2-methyl octane 62016-18-6 1.015 

13 4.820 A 37.7 H 5-methyl decane 13151-35-4 1.315 

14 4.859 A 42.1 H 4-methyl decane 2847-72-5 1.134 

15 4.902 A 35.4 H 2-methyl decane 6975-98-0 1.529 

16 4.980 A 44.1 H 3-methyl decane 13151-34-3 1.583 

17 5.312 A 50.1 H n-undecane 1120-21-4 2.420 

c 5.484 A NA M x-methyl undecane NA 1.590 

18 5.664 A 11.9 M 3-methyl undecane 1002-43-3 1.15 

19 5.906 A 37.3 H 5-methyl undecane 1632-70-8 1.696 

20 5.949 A 29.5 H 4-methyl undecane 2980-69-0 1.045 

21 5.996 A 15.1 M 2-methyl undecane 7045-71-8 1.072 

22 6.074 A 7.9 U 2,3-dimethyl undecane 17312-77-5 1.213 

23 6.387 A 43.9 H n-dodecane 112-40-3 2.595 

d 6.606 A 8.3 M 4-methyl dodecane 6117-97-1 0.929 

e 6.668 A NA H x-methyl dodecane NA 0.744 

24 7.024 S 28.7 H 2-methyl dodecane 1560-97-0 1.293 

25 7.094 S NA M x-methyl dodecane NA 1.281 

28 7.383 A 36.0 H n-tridecane 629-50-5 1.739 

f 7.923 A 8.7 U 4-methyl tridecane 26730-12-1 0.836 

29 7.970 A 9.8 U 6-propyl tridecane 55045-10-8 1.052 

30 8.040 A NA M x-methyl tridecane NA 1.066 

31 8.306 A 23.3 H n-tetradecane 629-59-4 1.562 

32 8.396 A NA M x-methyl tetradecane NA 1.198 

g 8.490 S 6.4 M 5-methyl tetradecane 25117-32-2 0.720 

33 8.728 S 10.2 H n-pentadecane 629-62-9 1.032 

H 9.232 A NA M x-methyl tetradecane NA 0.727 

5
Table 3. A summary of the hydrocarbon type analysis as provided by ASTM D-2789, for Jet-A4658 and S-8-4734. 

Fluid Paraffins 

Vol % 

Monocycloparaffins 

Vol % 

Dicycloparaffins 

Vol % 

Alkylaromatics 

Vol % 

Indanes 

and 

tetralins 

Vol % 

Naphthalenes 

Vol % 

Jet-A4658 46.5 22.5 5.4 18.4 4.5 2.4 

S-8- 

4734 80.0 17.3 0.9 0.1 0 1.9 

Especially striking is the paraffin content, which for S-8 is 80 % as compared with 46.5 % for 

Jet-A. Also striking is the difference in the aromatic fraction (which is consistent with the 

observation made earlier from the detailed analyses presented in Tables 1 and 2). The alkylaromatic content result for Jet-A was 18.4 %, while for S-8 it is negligible. In addition, S-8 has 

no discernable indanes or tetralins by ASTM-D-2789. 

3. Distillation Curves of Jet-A + S-8 

One of the most important methods of characterizing complex fluids is the measurement of the 

distillation curve. Simply stated, the distillation curve is a plot of the distillation temperature of 

the fluid plotted against the volume fraction distilled [6]. We have recently introduced an 

advanced approach to the measurement of the distillation curve that takes the information 

content to a much higher level [7-14]. The new metrology provides: 

• actual onset of boiling temperatures (the vapor rising temperature), 

• a composition explicit data channel for each distillate fraction (for both qualitative 

and quantitative analysis), 

• temperature measurements that are true thermodynamic state points, termed Tk

• the energy content of each distillate fraction, 

• consistency with a century of historical data, presented as Th

• explicit identification of azeotropes in fractions, 

• trace chemical analysis of each distillate fraction, and 

• corrosivity assessment of each distillate fraction. 

Distillation curves were measured for several mixtures of Jet-A + S-8 (25/75, 50/50 and 75/25, 

Jet-A + S-8, vol/vol). The mixture concentrations listed are nominal values mainly for 

identification purposes, however the uncertainty in preparation of the mixtures with mixing 

cylinders was 0.1 mL. The onset of boiling behavior of the mixtures is presented first in Table 4. 

In this table, the temperatures have been corrected to what would be obtained at 1 atmosphere, 

with the modified Sidney Young equation [6, 15-17]: 

 Cc = C(760 – Pa)(273 + Tc), 

6
Table 4. The onset of boiling behavior for three mixtures of Jet-A + S-8. 

Observed 

temperature,

°C 

S-8 75/25 S-8 

+ Jet-A 

50/50 S-8 

+ Jet-A 

25/75 S-8 + 

Jet-A 

Jet-A 4658 

Onset 163.0 160.9 154.9 161.8 139.9 

Sustained 168.6 182.3 178.6 178.9 185.6 

Vapor rising 181.9 184.8 186.6 189.1 190.5 

where Cc is the correction added to the observed temperature, C is a constant, 0.00012, Pa is the 

atmospheric pressure in millimeters of mercury, and Tc is the measured temperature in 

centigrade. In fact, the original Sidney Young equation specifies that Cc is dependent upon the 

average hydrocarbon chain length of the fluid, ranging from 0.000135 for a single carbon to 

0.000119 for 8 carbons. A linear correlation of these factors can be used to predict a value for 

simple fluids. In this work, C was set to 0.000109 [15-17], a value that corresponds to a carbon 

chain of 12. The actual experimental pressures were 83.5 kPa, 82.4 kPa, and 83.7 kPa for the 

75/25, 50/50, and 25/75 mixtures, respectively. From these data and the corrected temperatures, 

one can recover the raw measured temperatures with the Sidney Young equation. 

Representative distillation curve data for the three mixtures of Jet-A with S-8, along with data for 

the starting materials, are presented in Table 5. In this table we provide both Tk and Th (where Tk

is measured directly in the fluid while Th is measured in the distillation head). The Tk value is a 

true thermodynamic state point that can be modeled theoretically, while the Th data allow 

comparison with earlier measurements made with typical distillation curve instrumentation. In 

this table, the estimated uncertainty in the temperatures (with a coverage factor k = 2) is 0.1 °C. 

Note that the experimental uncertainty of Tk is actually somewhat lower than that of Th, but as a 

conservative position, we use the higher value for both temperatures. The uncertainty in the 

volume measurement that is used to obtain the distillate volume fraction is 0.05 mL in each case. 

The distillation curves based on the data from Table 5 are presented in Figure 1. The shapes of 

all of the curves are of the subtle sigmoid type that one would expect for a highly complex fluid 

with many components, distributed over a large range of relative molecular mass. There is no 

indication of the presence of azeotropic constituents, since there is an absence of multiple 

inflections and curve flattening. 

The relationship between Tk and Th is presented in Figure 2, in which both temperatures are 

presented for the mixture data shown in Table 2. We note that Tk always leads Th. This behavior 

is consistent with a complex mixture with a continually changing composition. Note that when 

these two temperatures converge, it is evidence of either a single component being generated (by 

vaporization) in the kettle, or the presence of an azeotrope that controls the composition of both 

phases. The absence of such a convergence in Figure 2 can be interpreted as further evidence of 

the absence of azeotropic behavior. This is in contrast to what was observed for the gasoline 

oxygenates, in which the convergence of Tk and Th (due to azeotrope formation) was observed 

[12]. 

7
Figure 2. The relationship of Tk and Th for the three mixtures of S-8 + Jet-A-4658 measured in 

this work. 

9
While the gross examination of the distillation curves is instructive and valuable for many design 

purposes, the composition channel of the advanced approach can provide even greater 

understanding and information content. One can sample and examine the individual fractions as 

they emerge from the condenser, as discussed in the introduction. Following the analytical 

procedure described, samples were collected and prepared for analysis. Chemical analyses of 

each fraction were done by gas chromatography with flame ionization detection and mass 

spectrometric detection. Representative chromatograms (measured by flame ionization detection) 

for each fraction of Jet-A-4658 are shown in Figure 3. The time axis is from 0 to 12 min for each 

chromatogram, and the abundance axis is presented in arbitrary units of area counts (voltage 

slices). It is clear that although there are many peaks on each chromatogram (30 to 40 major 

peaks, and 60 to 80 minor and trace peaks), these chromatograms are much simpler than those of 

the neat fluids, which can contain 300 to 400 peaks. At the very start of each chromatogram is 

the solvent front, which does not interfere with the sample. One can follow the progression of the 

chromatograms in Figure 3 as the distillate fraction becomes richer in the heavier components. 

This figure illustrates just one chemical analysis strategy that can be applied to the distillate 

fractions. It is possible to use any analytical technique that is applicable to solvent-borne liquid 

samples that might be applicable to a given application. 

The distillate fractions of the three Jet-A + S-8 mixtures, along with the starting Jet-A and S-8 

fluids, were examined for hydrocarbon types by use of a mass spectrometric classification 

method summarized in ASTM Method D-2789 [5]. The results of these hydrocarbon type 

analyses are presented in Tables 6a to 6d, and plotted in Figure 4. The first line in each of the 

tables reports the results of the analysis as applied to the entire sample (called the composite) 

rather than to distillate fractions. The data listed in this line are actually averages of two separate 

determinations; one done with a neat sample of the fuel (that is, with no added solvent) and the 

other with the sample in n-hexane. The volume of the neat sample was 0.2 μL, and only these 

mass spectra were corrected for sample volume. All of the distillate fractions presented in the 

table were measured in the same way as the composite (m/z range from 15 to 550 RMM units 

gathered in scanning mode, each spectrum corrected by subtracting trace air and water peaks). 

In general, the hydrocarbon type fractions for the composite (the first row in each table) are 

consistent with the compositions obtained for the distillate fractions (the remaining rows of each 

table). Thus, taking the S-8 fluid as an example, the paraffin fraction for the composite sample 

was found to be 80.0 %, while the fractions ranged from 79.1 to 87.8. We have noted, however, 

that with the composite samples (which naturally produce a much more complex total ion 

chromatogram), one obtains many more non-integral m/z peaks on the mass spectrum. Thus, for 

a distillate fraction, one might obtain a peak at m/z = 43.0, while for the composite one might 

obtain m/z = 43.0, 43.15, etc., despite the resolution of the instrument being only 1 unit of mass. 

Our practice has been to round the fractional masses to the nearest integral mass, a practice that 

can sometimes cause bias. This is an unavoidable vagary of the instrument that can potentially be 

remedied with a higher resolution mass spectrometer. We maintain that the comparability among 

the distillate fractions is not affected by this characteristic, although the intercomparability 

between the distillate fractions and the composite should be approached with a bit more caution. 

10
Figure 3. Chromatograms of distillate fractions of Jet-A-4658, presented in arbitrary units of 

intensity (from a flame ionization detector) plotted against time. 

11
Table 6. Summary of the results of hydrocarbon family calculations based on the method of 

ASTM D-2789. 

Table 6a. 75/25 S-8/Jet-A. 

Distillate 

volume 

fraction, 

% 

Paraffins 

Vol % 

Monocycloparaffins 

Vol % 

Dicycloparaffins 

Vol % 

Alkylaromatics 

Vol % 

Indanes 

and 

tetralins 

Vol % 

Naphthalenes 

Vol % 

Composite 75.3 22.0 0.4 1.2 0.2 0.9 

0.025 74.1 22.2 0.2 3.2 0.0 0.3 

10 77.9 19.1 0.1 2.6 0.0 0.3 

20 76.7 19.9 0.1 2.9 0.0 0.4 

30 76.6 20.0 0.1 2.9 0.0 0.5 

35 77.6 19.2 0.1 2.7 0.0 0.4 

40 75.9 20.1 0.3 3.0 0.2 0.6 

45 81.5 16.3 0.0 1.9 0.0 0.2 

50 78.1 18.9 0.2 2.3 0.1 0.5 

60 78.9 18.4 0.1 1.7 0.1 0.7 

70 72.3 21.6 1.4 2.3 0.8 1.6 

80 84.1 15.2 0.0 0.1 0.0 0.6 

Residue 83.1 16.5 0.0 0.0 0.0 0.4 

Table 6b. 50/50 S-8/Jet-A. 

Distillate 

volume 

fraction, 

% 

Paraffins 

Vol % 

Monocycloparaffins 

Vol % 

Dicycloparaffins 

Vol % 

Alkylaromatics 

Vol % 

Indanes 

and 

tetralins 

Vol % 

Naphthalenes 

Vol % 

Composite 65.4 23.5 6.1 8.8 3.0 2.3 

0.025 66.7 22.9 0.4 9.6 0.0 0.3 

10 67.9 23.3 0.5 7.8 0.2 0.4 

20 68.9 22.3 0.5 7.7 0.2 0.4 

30 70.6 20.9 0.3 7.4 0.3 0.5 

35 70.8 20.9 0.4 7.1 0.3 0.4 

40 71.3 20.5 0.4 6.8 0.4 0.6 

45 73.2 19.3 0.3 6.4 0.3 0.5 

50 71.9 20.0 0.4 6.2 0.8 0.8 

60 70.4 21.7 0.6 5.2 1.1 1.0 

70 73.1 20.9 0.4 3.4 1.0 1.2 

80 76.9 19.4 0.1 1.5 0.9 1.2 

Residue 72.3 25.9 0.3 0.2 0.1 1.2 

12
Table 6c. 25/75 S-8/Jet-A. 

Distillate 

volume 

fraction, 

% 

Paraffins 

Vol % 

Monocycloparaffins 

Vol % 

Dicycloparaffins 

Vol % 

Alkylaromatics 

Vol % 

Indanes 

and 

tetralins 

Vol % 

Naphthalenes 

Vol % 

Composite 48.1 25.6 8.5 11.3 4.2 2.5 

0.025 56.2 26.5 1.3 15.3 0.4 0.3 

10 56.7 25.1 1.5 15.5 0.7 0.5 

20 60.9 22.3 0.7 15.2 0.5 0.5 

30 56.7 24.6 1.8 14.5 1.6 0.8 

35 58.1 23.9 1.5 14.1 1.6 0.8 

40 57.0 24.9 1.9 13.3 1.9 1.0 

45 59.9 23.6 1.2 12.4 1.8 1.1 

50 60.7 23.4 1.3 11.5 1.9 1.2 

60 65.5 21.5 0.6 8.9 2.1 1.4 

70 62.4 24.9 1.3 6.9 2.6 1.9 

80 59.9 27.1 2.7 4.9 3.0 2.4 

Table 6d. Jet-A 4658. 

Distillate 

volume 

fraction, 

% 

Paraffins 

Vol % 

Monocycloparaffins 

Vol % 

Dicycloparaffins 

Vol % 

Alkylaromatics 

Vol % 

Indanes 

and 

tetralins 

Vol % 

Naphthalenes 

Vol % 

Composite 46.5 22.5 5.4 18.4 4.5 2.4 

0.025 40.4 27.3 3.4 27.3 1.2 0.5 

10 39.8 25.1 4.5 27.2 2.6 0.8 

20 41.2 24.6 4.4 25.6 3.1 1.1 

30 40.9 25.2 5.8 22.1 4.3 1.6 

35 43.2 24.5 4.3 21.9 4.2 1.8 

40 43.3 25.3 4.8 20.0 4.6 2.0 

45 41.7 25.9 6.4 18.7 5.0 2.3 

50 42.9 25.8 5.6 18.1 5.1 2.4 

60 43.1 26.4 6.7 15.0 5.9 2.9 

70 43.8 27.1 7.4 11.8 6.3 3.6 

80 48.7 29.9 7.0 6.3 4.6 3.3 

Residue 49.7 31.9 7.0 3.4 3.4 4.5 

13
Table 6e. S-8. 

Distillate 

volume 

fraction, 

% 

Paraffins 

Vol % 

Monocycloparaffins 

Vol % 

Dicycloparaffins 

Vol % 

Alkylaromatics 

Vol % 

Indanes 

and 

tetralins 

Vol % 

Naphthalenes 

Vol % 

Composite 80.0 17.3 0.9 0.1 0 1.9 

0.025 79.1 18.4 0.1 1.8 0.0 0.6 

10 81.2 16.4 0.0 1.9 0.0 0.5 

20 81.0 18.0 0.1 0.0 0.0 0.9 

30 80.8 17.9 0.3 0.0 0.0 1.1 

35 82.0 16.8 0.1 0.0 0.0 1.1 

40 85.8 13.7 0.0 0.0 0.0 0.5 

45 87.8 11.9 0.0 0.0 0.0 0.3 

50 85.3 13.8 0.0 0.0 0.0 0.9 

60 85.1 13.9 0.0 0.0 0.0 1.1 

70 85.1 13.7 0.0 0.0 0.0 1.2 

80 83.6 15.0 0.0 0.0 0.0 1.4 

Residue 84.8 14.7 0.0 0.0 0.0 0.5 

The distribution of hydrocarbon type as a function of distillate fraction is instructive among the 

different turbine fuel mixtures. Mixtures that have a high concentration of S-8 are seen to have a 

very high paraffin content, as expected. This approximate concentration ranges from 75+ % for 

the mixture that contains 75 % S-8, to 55+ % for the mixture that only contains 25 % S-8. For 

each mixture, the alkylaromatic content decreases markedly as a function of distillate fraction, 

and this is especially notable for the mixtures that are rich in Jet-A. For the 75/25 S-8/Jet-A 

mixture, the alkylaromatic concentration shows a great deal of scatter which results from its very 

low concentration in mixtures rich in S-8. The concentrations of the indanes and tetralins, and 

the naphthalenics compounds increase with distillate fraction, and this increase is especially 

pronounced in the mixtures that are rich in Jet-A. 

4. Density (at Atmospheric Pressure) for 50/50 Jet-A + S-8 

A Stabinger viscodensimeter (Anton Paar SVM 3000, see Figure 5 below) was used to determine 

the density in the temperature range from −40 °C to 100 °C (233.15 K to 373.15 K) at 

atmospheric pressure (83 kPa at 1654.7 m altitude at Boulder, Colorado). A similar technique 

was used for measurements on JP-10 and S-8 [18, 19]. The digital density analyzer in the 

viscodensimeter used a U-shaped vibrating sample tube and a system for electronic excitation 

and frequency counting. The density of the sample liquid in the vibrating tube was obtained from 

the resonant frequency of the vibrating system relative to the resonant frequency with a 

calibration liquid of known density. 

14
Figure 4. A plot of the hydrocarbon types resulting from the ASTM D-2789 analysis for three 

mixtures of Jet-A-4658 and S-8. 

15
The combination of a viscometer and a densimeter makes it possible to obtain absolute viscosity 

η as well as kinematic viscosity, ν (which will be presented later in this report) of a sample 

because ν = η/ρ where ρ is the density. The amount of sample needed for both measuring cells 

was less than 5 mL. The assembly is thermostatted by a copper block that surrounds both the 

viscosity and the density measuring cells and kept both cells at the same temperature. A 

thermoelectric heating and cooling system ensured the temperature stability of the copper block 

within 0.005 °C from the set temperature at the position of the viscosity cell over the whole 

temperature range. At temperatures below 0 °C the viscodensimeter was cooled with an 

additional external circulator. The uncertainty (k = 2; 95 % confidence level) of the temperature 

calibration was no more than 0.03 °C over the range from 15 to 100 °C. Outside this range the 

calibration uncertainty is no more than 0.05 °C. The density measurements performed with this 

instrument on the 50/50 (vol/vol) Jet-A + S-8 mixture are provided in Table 7. 

Figure 5. Main components of the Stabinger viscodensimeter SVM 3000. (1) Thermostatting 

Peltier block, (2) Concentric cylinder viscometer, (3) Vibrating tube densimeter. 

16
Table 7. Densities of 50/50 (vol/vol) Jet-A + S-8 mixture measured with the Stabinger 

viscodensimeter SVM 3000. The ambient pressure during the measurements was 83 kPa. 

Temperature Density Temperature Density Temperature Density

T ρ T ρ T ρ

K kg·m-3 K kg·m-3 K kg·m-3

373.15 719.5 373.16 719.6 373.15 719.9

363.15 727.1 363.15 727.2 363.15 727.2

353.15 734.6 353.15 734.6 353.15 734.8

343.15 742.1 343.15 742.2 343.15 742.2

333.15 749.5 333.15 749.5 333.15 749.5

331.15 750.9 331.15 750.8 331.15 750.9

329.15 752.3 329.15 752.3 329.15 752.3

327.15 753.8 327.15 753.8 327.15 754.0

325.15 755.3 325.15 755.3 325.15 755.5

323.15 756.8 323.15 756.8 323.15 756.8

321.15 758.3 321.15 758.2 321.15 758.3

319.15 759.8 319.15 759.7 319.15 759.8

317.15 761.3 317.15 761.2 317.15 761.3

315.15 762.7 315.15 762.6 315.15 762.7

313.15 764.2 313.15 764.0 313.15 764.2

303.15 771.2 303.15 771.3 303.15 771.3

293.15 778.5 293.15 778.6 293.15 778.5

283.15 785.8 283.15 785.9 283.15 785.8

273.15 793.0 273.15 793.1 273.15 793.1

271.15 794.5 271.15 794.5 271.15 794.6

269.15 795.9 269.15 795.9 269.15 796.0

267.15 797.4 267.15 797.4 267.15 797.4

265.15 798.8 265.15 798.9 265.15 798.9

263.15 800.2 263.15 800.3 263.15 800.3

261.15 801.7 261.15 801.7 261.15 801.7

259.15 803.1 259.15 803.1 259.15 803.1

257.15 804.5 257.15 804.6 257.15 804.6

255.15 805.9 255.15 806.0 255.15 806.0

253.15 807.3 253.15 807.4 253.15 807.4

251.15 808.8 251.15 808.7 251.15 808.8

249.15 810.2 249.15 810.2 249.15 810.2

247.15 811.6 247.15 811.6 247.15 811.6

245.15 813.0 245.15 813.0 245.15 813.0

243.15 814.4 243.15 814.5 243.15 814.4

241.15 815.8 241.15 815.8 241.15 815.8

239.15 817.3 239.15 817.3 239.15 817.2

237.15 818.7 237.15 818.7 237.15 818.6

235.15 820.0 235.15 820.1 235.15 820.0

233.15 821.4 233.15 821.5 233.15 821.4

Sample 1 

Run 1

Sample 2 

Run 1

Sample 3 

Run 1

17
710

730

750

770

790

810

830

230 240 250 260 270 280 290 300 310 320 330 340 350 360 370 380/ 

 ρ / kg·m3

Density of Jet-A + S-8

p = 83 kPa

T / K

Figure 6. The density of the 50/50 (vol/vol) mixture of Jet-A + S-8 as a function of temperature 

at atmospheric (ambient) pressure. 

18
Table 8. The measured viscosity of the 50/50 (vol/vol) mixture of Jet-A + S-8 at 83.4 kPa. 

Temperature 

T

Absolute 

Viscosity η

Kinem. 

Viscosity 

ν

Temperature 

T

Absolute 

Viscosity 

η

Kinem. 

Viscosity 

ν

Temperature 

T

Absolute 

Viscosity η

Kinem. 

Viscosity 

ν

K mPa·s mm2·s-1 K mPa·s mm2·s-1 K mPa·s mm2·s-1

Run 1 Run 2 Run 3

373.15 

363.15 

353.15 

343.15 

333.15 

331.15 

329.15 

327.15 

325.15 

321.15 

319.15 

317.15 

315.15 

303.15 

283.15 

273.15 

271.15 

269.15 

267.15 

265.15 

263.15 

261.15 

259.15 

257.15 

255.15 

253.15 

251.15 

249.15 

247.15 

245.15 

243.15 

241.15 

239.15 

237.15 

235.15 

233.15 

0.5217 

0.5794 

0.6489 

0.7297 

0.8254 

0.8483 

0.8705 

0.8936 

0.9177 

0.9690 

0.9964 

1.025 

1.055 

1.272 

1.842 

2.310 

2.427 

2.554 

2.692 

2.842 

3.007 

3.187 

3.385 

3.603 

3.844 

4.110 

4.405 

4.735 

5.103 

5.516 

5.981 

6.435 

7.030 

7.706 

8.478 

9.363 

0.7251 

0.7969 

0.8833 

0.9832 

1.101 

1.130 

1.157 

1.185 

1.215 

1.278 

1.311 

1.347 

1.383 

1.649 

2.344 

2.912 

3.054 

3.208 

3.376 

3.558 

3.758 

3.976 

4.215 

4.479 

4.770 

5.091 

5.447 

5.844 

6.288 

6.784 

7.343 

7.888 

8.601 

9.413 

10.34 

11.40 

373.16 

363.15 

353.15 

343.15 

333.15 

331.15 

329.15 

327.15 

325.15 

321.15 

319.15 

317.15 

315.15 

303.15 

283.15 

273.15 

271.15 

269.15 

267.15 

265.15 

263.15 

261.15 

259.15 

257.15 

255.15 

253.15 

251.15 

249.15 

247.15 

245.15 

243.15 

241.15 

239.15 

237.15 

235.15 

233.15 

0.5216 

0.5797 

0.6493 

0.7304 

0.8263 

0.8488 

0.8710 

0.8942 

0.9184 

0.9700 

0.9975 

1.026 

1.056 

1.272 

1.843 

2.309 

2.427 

2.554 

2.692 

2.843 

3.008 

3.189 

3.387 

3.605 

3.844 

4.111 

4.405 

4.735 

5.103 

5.516 

5.981 

6.436 

7.030 

7.706 

8.478 

9.363 

0.7247 

0.7972 

0.8839 

0.9841 

1.102 

1.130 

1.158 

1.186 

1.216 

1.279 

1.313 

1.348 

1.385 

1.650 

2.345 

2.912 

3.054 

3.208 

3.376 

3.558 

3.759 

3.978 

4.217 

4.481 

4.769 

5.091 

5.446 

5.844 

6.288 

6.784 

7.343 

7.888 

8.602 

9.413 

10.34 

11.40 

373.15 

363.15 

353.15 

343.15 

333.15 

331.15 

329.15 

327.15 

325.15 

321.15 

319.15 

317.15 

315.15 

303.15 

283.15 

273.15 

271.15 

269.15 

267.15 

265.15 

263.15 

261.15 

259.15 

257.15 

255.15 

253.15 

251.15 

249.15 

247.15 

245.15 

243.15 

241.15 

239.15 

237.15 

235.15 

233.15 

0.5213 

0.5796 

0.6492 

0.7302 

0.8263 

0.8500 

0.8724 

0.8956 

0.9199 

0.9716 

0.9991 

1.028 

1.058 

1.273 

1.844 

2.315 

2.432 

2.560 

2.698 

2.849 

3.014 

3.195 

3.394 

3.612 

3.853 

4.121 

4.417 

4.748 

5.117 

5.531 

5.997 

6.453 

7.049 

7.727 

8.500 

9.388 

0.7241 

0.7971 

0.8836 

0.9839 

1.102 

1.132 

1.160 

1.188 

1.218 

1.281 

1.315 

1.350 

1.387 

1.651 

2.347 

2.918 

3.061 

3.215 

3.383 

3.567 

3.767 

3.986 

4.226 

4.490 

4.781 

5.104 

5.462 

5.860 

6.305 

6.803 

7.363 

7.910 

8.625 

9.438 

10.37 

11.43 

20
0.4

0.2

0

0.2

0.4

0.6

0.8

1.0

1.2

230 250 270 290 310 330 350 370

log10( / mm2·s-1)

T / K

Kinematic Viscosity

of Jet-A + S-8

p = 83 kPa 10 mm2

·s-1

1 mm2·s-1

Figure 8. A plot of the kinematic viscosity of the 50/50 mixture of Jet-A + S-8.

21
0.4

0.2

0

0.2

0.4

0.6

0.8

1.0

1.2

230 250 270 290 310 330 350 370

log10( / mPa·s)

T / K

Absolute Viscosity

of Jet-A + S-8

10 mPa·s p = 83 kPa

1 mPa·s

Figure 9. A plot of the absolute viscosity of the 50/50 mixture of Jet-A + S-8.

22
6. Speed of Sound Measurements (at Atmospheric Pressure) for 50/50 Jet-A + S-8 

The speed of sound in liquid samples of S-8 was measured with a sound speed analyzer DSA 

5000 that is similar to the SVM 3000 viscodensimeter in design and appearance. It also includes 

a vibrating U-tube densimeter and a pulse-echo speed of sound measurement cell that is 

illustrated below. However, the temperature range is limited from 0 °C to 70 °C. The 

measurement uncertainty is stated for both properties as 0.01 % to 0.1 %, with repeatabilities of 

0.001 kg·m-3 in the density and 0.1 m·s-1 in the speed of sound measurement. The density 

measurement in the DSA 5000 is more accurate than that in the viscodensimeter. By design, the 

densimeter in the viscodensimeter was made only as accurate as necessary in view of the higher 

uncertainty of the viscosity measurement. This device is shown schematically in Figure 10. The 

measured values for the speed of sound in the mixture of Jet-A + S-8 are provided in Table 9, 

and a plot of these values against temperature is provided in Figure 11. Adiabatic compressibilities were obtained from the measured densities and speeds of sound via the thermodynamic 

relation κs = −(∂V/∂p)s/V = 1 / (ρ w

2

), where V denotes volume, p is pressure, and w the speed of 

sound. Subscript s indicates “at constant entropy s.” The calculated values are also reported in 

Table 9 and they are plotted in Figure 12.

Transmitter

Length

~ 5mm

Receiver

Period of the

sound speed cell

Electronics

Figure 10. Schematic of the sound speed measurement in the DSA 5000. 

23
Table 9. Speeds of sound and adiabatic compressibilities of Jet-A + S8 mixture measured in the 

Sound Speed Analyzer DSA 5000. The ambient pressure during the measurements was 83 kPa. 

Temperature 

T

Speed of 

sound 

w

Adiab. 

compressibility κs

Temperature 

T

Speed of 

sound 

w

Adiab. 

compressibility κs

Temperature 

T

Speed of 

sound 

w

Adiab. 

compressibility κs

K m·s-1 TPa-1 K m·s-1 TPa-1 K m·s-1 TPa-1

Run 1 Run 2 Run 3

343.15 

333.15 

323.15 

313.15 

303.15 

293.15 

283.15 

278.15 

1113.14 

1149.68 

1186.39 

1223.58 

1261.50 

1299.99 

1338.99 

1358.70 

1090.16 

1011.70 

940.620 

875.581 

815.544 

760.250 

709.230 

685.285 

343.15 

333.15 

323.15 

313.15 

303.15 

293.15 

283.15 

278.15 

1111.09 

1147.65 

1184.76 

1222.25 

1260.38 

1299.10 

1338.40 

1358.00 

1094.00 

1015.14 

943.116 

877.310 

816.698 

760.929 

709.468 

685.069 

343.15 

333.15 

323.15 

313.15 

303.15 

293.15 

283.15 

278.15 

1109.43 

1145.94 

1183.18 

1220.87 

1259.13 

1298.02 

1337.51 

1356.78 

1097.51 

1018.36 

945.796 

879.508 

818.562 

762.394 

710.520 

685.217 

24
1050

1100

1150

1200

1250

1300

1350

1400

270 280 290 300 310 320 330 340 350

w / m·s-1

T / K

Speed of Sound

of Jet-A + S-8

p = 83 kPa

Figure 11. A plot of the speed of sound in a 50/50 mixture of Jet-A + S-8.

25
650

700

750

800

850

900

950

1000

1050

1100

1150

270 280 290 300 310 320 330 340 350

T / K

Adiabatic Compressibility

of Jet-A + S-8

p = 83 kPa

 s / TPa-1

Figure 12: A plot of the adiabatic compressibility of a 50/50 mixture of Jet-A + S-8. 

26
7. Correlations for the Density, Viscosity, and Speed of Sound of 50/50 Jet-A + S-8 

The previously reported experimental results for the density, viscosity, and speed of sound of 

50/50 Jet-A + S-8 at ambient pressure were correlated to facilitate their practical application. The 

temperature dependence of the density and of the speed of sound is each represented by a 

quadratic polynomial 

a0 a1T a2T2, and (1) 

w c0 c1T c2T2, (2) 

 

while the temperature dependence of the absolute viscosity requires the more complex 

formulation 

0

 exp 1

2

Tr

3 ln(Tr) 4Tr 5

 

 

 . (3) 

The adjustable parameters in eqs. (1) and (2) were determined by linear and those in eq. (3) by 

nonlinear least squares regression. The optimal values are listed in Table 10 with their standard 

deviations and the applicable temperature ranges. 

Table 10: Parameter values and associated standard deviations of the correlations eqs. (1-3) for 

a 50/50 mixture of Jet-A + S-8. 

Density, eq. (1) Viscosity, eq. (3) Speed of sound, eq. (2) 

233 K ≤ T ≤ 373 K 233 K ≤ T ≤ 373 K 278 K ≤ T ≤ 343 K

i

Parameter 

value 

ai

Stand. 

Dev. 

si

Parameter 

value 

βi

Stand. 

Dev. 

si

Parameter 

value 

ci

Stand. 

Dev. 

si

0 

1 

2 

3 

4 

5 

976.37964 

-0.62516115 

-1.6811101·10-4

0.44 

3.0·10-3

5.2E·10-6

8.0698334 

-8.9055146 

-8.4990463 

1.6747087 

-4.2001948 

0.58 

0.68 

0.39 

0.10 

0.075 

2659.2926 

-5.3967658 

2.5802235·10-3

56 

0.37 

5.9·10-4

Max. dev. 

Min. dev. 

Avg. abs. dev. 

Std. dev.

0.029 % 

-0.028 % 

0.0076 % 

0.0098 %

0.69 % 

-0.61 % 

0.20 % 

0.26 %

0.073 % 

-0.046 % 

0.026 % 

0.031 %

27
8. Compressed Liquid Density Measurements for 50/50 Jet-A + S-8 

A schematic of the apparatus used to measure compressed liquid densities over the temperature 

range of 270 K to 470 K and to pressures of 50 MPa is illustrated in Figure 13. The heart of the 

apparatus is a commercial vibrating tube densimeter; however, several physical and procedural 

improvements have been implemented beyond that of the commercial instrument operated in a 

stand-alone mode. The densimeter is housed in a specially designed two-stage thermostat for 

improved temperature control. The uncertainty in the temperature is 0.02 K, with short-term 

stability of 0.005 K. Pressures are measured with an oscillating quartz crystal pressure transducer 

with an uncertainty of 10 kPa. The densimeter was calibrated with measurements of vacuum, 

propane and toluene, over the temperature and pressure range of the apparatus to achieve an 

uncertainty in density of 1 kg/m3. 

The apparatus was designed, and software was written so that the operation and data acquisition 

are fully automated. Data are taken along isotherms over a temperature/ pressure matrix 

programmed by the operator prior to the start of measurements. The electronically actuated 

pneumatic valves and programmable syringe pump are used to move from one pressure to the 

next and/or flush fresh sample through the system. Operation of the densimeter in this manner 

allows for measurements to be made 24 h per day. The densimeter described above has been 

used to measure 121 compressed liquid densities of a 50/50 (vol/vol) Jet-A + S-8 sample from 

270 K to 470 K at pressures from 0.5 MPa to 30 MPa. The data are listed in Table 11.

Figure 13. Schematic of the compressed liquid density apparatus. 

28
620

640

660

680

700

720

740

760

780

800

820

840

230 250 270 290 310 330 350 370 390 410 430 450 470 490

 kg·m3

Density of Jet-A + S-8 83 kPa Š p Š 30 MPa

T / K

Figure 14. Compressed liquid densities of Jet-A + S-8 50/50 (vol/vol) mixture as a function of 

temperature. The measurement results at ambient pressure are indicated by light grey symbols. 

29
Table 11. Compressed liquid density measurements on 50/50 Jet-A + S-8. 

Temperature 

[K] 

Pressure 

[MPa] 

Density 

[kg/m3] 

Temperature 

[K] 

Pressure 

[MPa] 

Density 

[kg/m3] 

270.00 30.018 812.15 370.00 4.007 726.14 

270.00 25.007 809.52 370.00 3.006 725.07 

270.00 20.017 806.83 370.00 2.011 723.99 

270.00 15.011 804.05 370.00 1.001 722.88 

270.00 10.013 801.19 370.00 0.508 722.33 

270.00 5.011 798.23 390.00 30.016 737.06 

270.00 4.001 797.61 390.00 25.013 732.73 

270.00 3.006 797.01 390.00 20.013 728.18 

270.00 2.006 796.39 390.00 15.005 723.33 

270.00 1.010 795.77 390.00 10.016 718.16 

270.00 0.515 795.45 390.00 5.013 712.56 

290.00 30.014 799.58 390.00 4.004 711.36 

290.00 25.004 796.73 390.00 2.998 710.14 

290.00 20.010 793.80 390.00 2.002 708.92 

290.00 15.002 790.76 390.00 1.006 707.68 

290.00 10.006 787.62 390.00 0.509 707.05 

290.00 5.014 784.35 410.00 30.011 724.65 

290.00 4.009 783.67 410.00 25.011 719.97 

290.00 3.010 782.98 410.00 20.000 714.98 

290.00 2.008 782.28 410.00 15.000 709.65 

290.00 1.010 781.58 410.00 10.007 703.88 

290.00 0.505 781.21 410.00 5.006 697.59 

310.00 30.004 786.80 410.00 4.009 696.25 

310.00 25.010 783.68 410.00 3.005 694.88 

310.00 20.010 780.45 410.00 2.005 693.47 

310.00 15.010 777.09 410.00 1.008 692.05 

310.00 10.004 773.59 410.00 0.509 691.32 

310.00 5.006 769.95 430.00 30.005 712.26 

310.00 4.007 769.18 430.00 25.007 707.16 

310.00 3.017 768.42 430.00 20.011 701.72 

310.00 2.006 767.60 430.00 15.011 695.85 

310.00 1.008 766.83 430.00 10.011 689.41 

310.00 0.503 766.42 430.00 5.014 682.31 

330.00 30.001 774.17 430.00 4.000 680.76 

330.00 25.004 770.79 430.00 3.010 679.21 

330.00 19.995 767.27 430.00 2.005 677.60 

330.00 15.003 763.61 430.00 1.006 675.95 

330.00 10.012 759.79 430.00 0.509 675.10 

330.00 5.002 755.76 450.00 29.993 700.02 

330.00 4.008 754.91 450.00 25.003 694.51 

330.00 3.012 754.07 450.00 20.012 688.55 

330.00 2.007 753.21 450.00 15.014 682.04 

330.00 1.006 752.34 450.00 10.010 674.85 

330.00 0.513 751.91 450.00 5.005 666.76 

30
Temperature 

[K] 

Pressure 

[MPa] 

Density 

[kg/m3] 

Temperature 

[K] 

Pressure 

[MPa] 

Density 

[kg/m3] 

350.00 30.002 761.73 450.00 4.006 665.01 

350.00 25.007 758.07 450.00 3.012 663.21 

350.00 20.006 754.24 450.00 2.001 661.33 

350.00 15.009 750.23 450.00 1.009 659.42 

350.00 10.017 746.02 450.00 0.501 658.41 

350.00 5.006 741.53 470.00 30.021 687.99 

350.00 4.015 740.60 470.00 25.004 681.96 

350.00 3.001 739.64 470.00 20.003 675.41 

350.00 2.006 738.69 470.00 14.995 668.18 

350.00 1.012 737.71 470.00 10.011 660.13 

350.00 0.508 737.21 470.00 5.013 650.91 

370.00 30.007 749.41 470.00 4.005 648.87 

370.00 25.009 745.44 470.00 3.007 646.76 

370.00 20.006 741.26 470.00 2.003 644.58 

370.00 15.011 736.85 470.00 1.006 642.31 

370.00 10.006 732.18 470.00 0.516 641.16 

370.00 5.004 727.18 

9. References 

[1] Handbook of aviation fuel properties, CRC Report No. 635, Alpharetta, GA: 

Coordinating Research Council (CRC) (2004). 

[2] MSDS, S-8 Synthetic Jet Fuel, material safety data sheet. Syntroleum Corp., Tulsa, OK 

(2005). 

[3] T. J. Bruno, P. D. N. Svoronos, CRC handbook of basic tables for chemical analysis, 2nd 

ed., Boca Raton: CRC Press (2004). 

[4] T. J. Bruno, P. D. N. Svoronos, CRC handbook of fundamental spectroscopic correlation 

charts. Boca Raton: Taylor and Francis CRC Press (2005). 

[5] Standard test method for boiling range distribution of petroleum fractions by gas 

chromatography, ASTM Standard D2789-02, ASTM Annual Book of Standards (2004). 

[6] Standard test method for distillation of petroleum products at atmospheric pressure, 

ASTM Standard D 86-04b, Book of Standards Volume 05.01. American Society for 

Testing and Materials: West Conshohocken, PA (2004). 

[7] T. J. Bruno, Method and apparatus for precision in-line sampling of distillate. Sep. Sci. 

Technol. 41(2): 309-314 (2006). 

[8] T. J. Bruno, Improvements in the measurement of distillation curves — part 1: a 

composition-explicit approach. Ind. Eng. Chem. Res. 45: 4371-4380 (2006). 

[9] T. J. Bruno, B. L. Smith, Improvements in the measurement of distillation curves—Part 

2: Application to aerospace/aviation fuels RP-1 and S-8. Ind. Eng. Chem. Res. 45: 4381-

4388, (2006). 

31
[10] T. J. Bruno, B. L. Smith, Enthalpy of combustion of fuels as a function of distillate cut: 

application of an advanced distillation curve method. Energy and Fuels 20: 2109-2116 

(2006). 

[11] B. L. Smith, T. J. Bruno, Advanced distillation curve measurement with a model 

predictive temperature controller. Int. J. Thermophys., 2006. 27: p. 1419-1434. 

[12] B. L. Smith, T. J. Bruno, Improvements in the measurement of distillation curves—Part 

3: Application to gasoline and gasoline + methanol mixtures. Ind. Eng. Chem. Res. 46: 

297-309 (2006). 

[13] B. L. Smith, T. J. Bruno, Improvements in the measurement of distillation curves—Part 

4: application to the aviation turbine fuel Jet-A. Ind. Eng. Chem. Res. 46: 310-320 

(2006). 

[14] B. L. Smith, T. J. Bruno, Application of a composition-explicit distillation curve 

metrology to mixtures of Jet-A + synthetic Fischer-Tropsch S-8. J. Propul. Power. 

(submitted). 

[15] S. Young, Correction of boiling points of liquids from observed to normal pressures. 

Proc. Chem. Soc. 81: 777 (1902). 

[16] S. Young, Fractional distillation. London: Macmillan and Co., Ltd. (1903). 

[17] S. Young, Distillation principles and processes. London: Macmillan and Co., Ltd. (1922). 

[18] T. J. Bruno, The properties of S-8. Final Report for MIPR F4FBEY6237G001, Air Force 

Research Laboratory (2006). 

[19] T. J. Bruno, M. L. Huber, A. Laesecke, E. W. Lemmon, R. A. Perkins, Thermochemical 

and thermophysical properties of JP-10. Natl. Inst. Stand. Technol. NISTIR 6640 (2006). 

32