Characterization data and a hydrocarbon compositional analysis are presented for a research test fuel designated as an experimental referee broadened-specification aviation turbine fuel. This research fuel, which is a special blend of kerosene and hydrotreated catalytic gas oil, is a hypothetical representation of a future fuel should it become necessary to broaden current kerojet specifications. It is used as a reference fuel in research investigations into the effects of fuel property variations on the performance and durability of jet aircraft components, including combustors and fuel systems

Prok, G. M.

Seng, G. T.

English

NASA Technical Reports Server

A/,,£,",_,-"_- ,7/¢'€',0
3 1176 00138 6854
NASA-TM-81440 19800009938
NASA Technical Memorandum 81440
INITIALCHARACTERIZATIONOF
ANEXPERIMENTALREFEREE
BROADENED-SPECIFICATION
(ERBS)AVIATIONTURBINEFUEL
George M. Prok and Gary T. Seng
Lewis Research Center
Cleveland, Ohio
January 1980
Q
https://ntrs.nasa.gov/search.jsp?R=19800009938 2020-03-21T19:54:21+00:00Z
Q
•,.
SUMMARY
Characterization data and a hydrocarbon compositional analysis are presented for
a research test fuel designated as an Experimental Referee Broadened-Specification
(ERBS) aviation turbine fuel. This research fuel, which is a special blend of kerosine
and hydrotreated catalytic gas oil, is a hypothetical representation of a future fuel
should it become necessary to broaden current kerojet specifications. It will be used
as a reference fuel in research investigations into the effects of fuel property varia-
tions on the performance and durability of jet aircraft components, including combus-
tors and fuel systems."
INTRODUCTION
Until recently there has been an abundance of mid-distillates from petroleum
available for jet fuel. Demand for jet fuel is increasing at a time when there is severe
competition for the available mid-distillates. A relaxation in property specifications
for future jet fuels could minimize potential curtailments in supplies and might also
lower costs. These future jet fuels may have higher aromatic content, higher freez-
ing point, lowe:- fuel volatility, higher viscosity, and poorer thermal stability. Pre-
sently a fuels data bank compiled by the Department of Energy (DOE) has shown a
trend of increaoing aromatics in jet fuels (ref. 1). Assessing the effect of changes in
jet fuel properties 2.1d developing technology to use the fuels will require a large effort
in combustor and engine testing. Such an effort is in progress at both NASA's Lewis
Research Center and 'Vdght-Patterson Air Force Base.
Requirements for an Experimental Referee Broadened-Specification (ERBS) avia-
tion turbine fuel were proposed at a workshop held at Lewis in 1977 (ref. 2). They
were written to avoid redundancy, to make it reasonably easy to supply the fuel, and
to give sufficiently reproducible combustion characteristics. These specifications for
a research fuel reflect the opinions of the subject workshop on what a future broad-
property fuel might be like. They are subject to change as a better understanding of
future feedstocks, processes, and product demand is obtahled. However, for the pre-
sent, a fuel with the proposed properties will serve as a reference or baseline fuel in
research investigations into the effects of fuel property variations on the performance
and durability of jet aircraft components, including cumbustors and fuel systems. A
technical panel sponsored by the Coordinating Research Council (CRC) (ref. 3) recom-
mended some slight modifications to the property requirements. The requirements
for the Experimental Referee Broadened-Specification aviation turbine fuel as suggested
by CRC are given in table!. Other experimental fuels of lower quality could be blends
of this fuel with a suitable blending stock.
This report gives the measured characteristics of the first acquisition of the ERBS c'
fuel proposed in reference 2. Blend composition is discussed so that future acquisi-
tions can preserve the "reference" characteristics of this fuel.
ERBS FUEL BLEND
The best method of obtaining ERBS fuel is directly from one stream of a refinery.
For this to occur is unlikely because refineries usually do not operate on a fixed crude
or crude blend. The next best method would be a blend of two refinery streams. At-
tempts to blend the fuel with only two refinery streams showed that the freezing point
and flash point specifications could not be readily achieved. The CRC recommended
that the flash point be modified from 1000±100 F to 380 C (1000 F) minimum and that the
freezing point be increased from _200 F to _230 C (_100 F) maximum. These changes
will not significantly affect the combustion characteristics of the fuel but will slightly
affect ignition, altitude relight, and low-temperature behavior.
The kerosine and hydrotreated catalytic gas oil (lICGO) streams at the Marcus Hook
refinery of the Sun Company were identified as suitable for blending ERBS fuel to table I
requirements. A mixture of about 65 percent kerosine and 35 percent HCGO is required
to blend ERBS fuel. Hydrogen content was the controlling factor in determining blend
composition. Sample blends made at different times met the requirements; however,
the sample blends showed that care must be taken to meet the freezing-point specifica-
tion. The available range of hydrogen content should be sufficient for adjusting the
blend to meet the freezing point specification.
An antioxidant additive and long-term storage under a blanket of gaseous nitrogen
are required for this fuel blend. The antioxidant to be used is an alkylated phenol spe-
cified in ASTM D-1655. The ERBS fuel analyzed for this report had no antioxidant.
ERBS FUEL CHARACTERIZATION
The test results of, the fuel reqUirements for, and the ~nalytical techniques used to
characterize the initial acquisition of 600 barrels of ERBS fuel are summarized in
table I. Several of the test methods were revised from those originally specified; the
revised methods include those for determining sulfur as mercaptan, total nitrogen,
naphthalenes, the hydrocarbon compositional analysis, and the distillation tempera-
tures.
2
•...
The weight percentage of mercaptan sulfur was determined by using the potentio-
metric method (ASTM D-3227) rather than the color-indicator method (ASTM D-1219),
since the latter has been discontinued. The total weight percentage of nitrogen was de-
termined by the combustor-microcoulometric method (ASTM D-3431) as a well-charac-
terized alternative to the Kjeldahl method.
Because of the relatively high concentration of naphthalenes in the fuel, ASTM
method D-1840 was slightly modified. The accuracy of the reported result is somewhat
in question because of the 3280 C (6220 F) final boiling point of the fuel. There is some
indication from mass spectrographic data that the 13.2 percent by volume (15.7 percent
I
by weight) naphthalene content reported had been elevated by the presence of interfering
compounds. The hydrocarbon compositional analysis was performed by group separa-
tion before instrumental analyses rather than by gas chromatography - mass spectrom-
etry (GCMS) as originally specified in reference 2. The separation was performed by
using a modification of the fluorescent indicator adsorption method (ASTM D-1319) fol-
lowed by gas chromatographic and mass spectrographic analyses of the alkane (satur-
ate) fraction and by mass spectrographic and nuclear magnetic resonance analyses of
the aromatic fraction. The results are presented in table II. The loss reported in
table Il(a) is primarily due to the more volatile components of the alkane (saturate)
fraction. Tables II (b) to (d) give the composition of the ERBS fuel and should serve as
a "fingerprint" for the fuel. Subsequent ERBS fuel blends should not vary significantly
from this composition.
The standard method for distilling petroleum products (ASTM D-86) was sufficient
to characterize the fuel and therefore was used instead of the standard method for dis-
tilling crude petroleum (ASTM D-2892). The distillation curve is shown in figure 1,
and selected distillation data are presented in table I.
A series of five trials at various temperatures between 237 .50 and 2600 C (460°
and 5000 F) were used to determine the ERBS fuel breakpoint temperature. A plot of
the results, figure 2, shows that the breakpoint temperature is at approximately 2560 C
(4830 F) if the breakpoint condition is defined by a spun TDR of 13 or by a test-filter
pressure drop of 25 mm Hg. No pressure drop was observed in any of the five trials.
The results of a selective ele .nental analysis by arc emission spectroscopy are
presented in table III. Sample treatment included ashing, dissolving the residue in a
solution of hydrochloric and nitric acid, and quantitatively spiking graphite electrodes
with the resulting solution. The accuracy of the analysis is approximately ±50 percent
pf the values reported. Those elements that were not detected are reported as "less
than" the method detection limits for the s2.!!lplp. The unchfl"racteristically high concen-
tration of lead was verified by atomic absorption spectroscopy but is believed to origi-
nate from the storage container rather than from the ERBS fuel itself .
3
CONCLUDING REMARKS
A source for ERBS aviation turbine fuel has been ioentified as a blend of the kero-
sine and hydrotreated catalytic gas oil (I-ICGO) streams from the Marcus Hook refinery
of the Sun Company. The blend is about 65 percent kerosine and 35 percent HCGO.
iThe freezing point specification is the most difficult to meet; however, the available
range for hydrogen content is sufficient for adjusting the blend to freezing point specifi-
:cations. The results of inspection data, including hydrocarbon compositional analysis
and metals analysis, are presented.
REFERENCES
i. Shelton, E. M.. Aviation Turbine Fuels, 1978. BETC/PPS-79/2, U.S. Department
of Energy, 1979.
2. Longwell, J. P., ed. : Jet Aircraft Hydrocarbon Fuels Technology. NASA CP-2033,
1977.
3. Coordinating Research Council Annual Report for Year Ending June 30, 1979, Coor-
dinating Research Council, Inc., Atlanta, Ga., p. 45.
5
9
TABLE I.- EXPERIMENTAL REFEREE BROADENED-SPECIFICATION (ERBS) AVIATION
TURBINE FUEL - REQUIREMENTS AND BLEND RESULTS
Property Blend results Requirements Test method
Composition:
Hydrogen, wt % 12.86 12.8_0.2 NMR
Atomatics, vol _ 35.0 Report ASTM D-1319
Sulfur,mercaptan, wt % 0.0005 0.003 max. ASTM D-3227
Sulfur,total,wt _ 0.085 0.3 max. ASTM D-1266
Nitrogen, total,wt _ 0.0054 Report ASTM D-3431
Naphthalenes,vol._ 13.2 Report ASTM D-1840
Hydrocarbon compositional analysis Table II Report GCMS a
Volatility:
Distillation temperature, °C (OF)
Initial boiling point 162 (324) Report ASTM D-86
10 Percent 188 (370) 204 (400)max.
50 Percent 215 (419) Report
90 Percent 279 (534) 260 (500) rain.
Finalboilingpoint 328 (622) Report
Residue, percent i.2 Report
Loss, percent 0.3 Report
Flash point, JC (OF) 60 (140) b38 (100) rain. ASTM D-56
Gravity,API (15° C) 37.1 Report ASTM D-287
Gravity,specific_5°/15° C) 0.8381 Report ASTM D=1298
Fluidity:
Freezing point,°C (OF) -29 (-20) b-23 (-10)max. ASTM D-2386
Viscosity,at-23° C (-10° F), cS 7.2 12 max. ASTM D-445
Net heatofcombustion,kJ/kg (Btu/Ib) 42 427 (18275) Report ASTM D--2382
thermal stability:
JFTOT, breakpointtemperature,°C (OF) 255.5 (492) 238 (460)rain. ASTM D-3241
(TDR, 13; and AP, 25 mm Hg)
aFor thispaper, testmethod was FIA spearationfollowedby group analysis.
bModified from that in ref. 2.
6TABLE II.- HYDROCARBON COMPOSITIONAL ANALYSIS RESULTS
(a) Modified FIA separation _) Normal paraffins in fuel by gas
by ASTM D-1319, in wt % chromatography, in wt %
....... 34.3 I C9 ...... 0.67 C15 ...... 0.73
Aromatics t.
Saturates ....... 60.8 ] .2.07 .0.61
Olefins ......... 0.0 [ C10 ..... C16 .....
Loss .......... 4.9 _ Cll ...... 2.68 C17 ...... 0.55
C12 ...... 2.43 C18 ...... 0.36
C13 ...... 1.64 C19 ...... 0.18
C14 ...... 0.85 C20 ...... 0.12
(c) Mass spectrometric group analysis by ASTM D-2425, in wt %
Saturate group Aromatic group
Paraffins ......... 37.1 Paraffins .............. 0.6
Noncondensed Cycloparaffins ........... 1.9
cycloparaffins ..... 17.7 Alkybenzenes ........... 10.8
Condensed Indanes and tetralins ........ 5.6
dicyeloparaffins ..... 4.7 Indenes and CN H(2 N _ 10) ..... 0.3
Condensed Naphthalenes ............ 0.0
tricyeloparaffins ..... 1.0 Alkynaphthalenes .......... 9.5
Alkybenzenes ....... 0.3 Benzothiophenes .......... 0.4
Acenaphthenes ........... 2.6
Fluorene .............. 1.3
Triaromaties ............ 1.4
(d)Nuclear magnetic resonance of aromatic fraction
Average molecular weight ........................ 190.2
Average molecular formula .................... C14.5H16.3
Aromaticity ................................. 0.62
Aromatic rings per molecule ....................... 1.7
Aromatic ring carbons per molecule ................... 8.9
Saturate carbon content, percent ............... _ ..... 38.2
Alkyl substituents per molecule ...................... 3.1
Carbons per alkyl substituent ....................... 1.8
Carbon-hydrogen ratio of alkyl groups .................. 5.55
Naphthenic carbon content, percent .................... 6.7
Naphthene rings per molecule ....................... 0.3
Naphthene rings per substituent .............. , ........ 0.1
Nonbridge aromatic ring carbon content, percent ............. 51.7
Nonbridge aromatic carbons per molecule ................ 7.5
Substitution of nonbridge aromatic carbons, percent ........... 43.2
Monoaromatie content, I)ercent ...................... 38.3
Diaromatic content, percent ........................ 49.8
Triaromaticcontent,percent ....................... 11.9
7J
TABLE III. - ELEMENTAL ANALYSIS
BY ARC EMISSION SPECTROSCOPY
Element Concentration,
ppm
A1 0.0005
As <0. O03
Ca 0.001
Cd <0.0004
Cr <0.0001
Cu 0.01
Fe 0.002
Mg 0.0002
Mn <0.0003
Mo 0.001
Na 0.003
Ni 0.002
P <0.Ol
Pb 0.08 (ao. 12)
Si 0.02
Sn 0.001
Ti <0. 0003
V 0.0008
Zn 0.001
avalue determined by atomic ab-
sorption spectroscopy.
350--
300 D
J
150 100
Volumerecovered,vol%
Figure1. - D-86distillationcurve.
0 0
• Br_kp0int
_ -
8--
i[__
o I I I
230 240 250 260
Temperature,°C
Figure2. - JFTOTbreakpointdetermination.
/;
1. Report No. I2. Government Accession No. 3. Recipient's Catalog No.
NASA TM-81440
4. Title and Subtitle 5. Report Date
INITIAL CHARACTERIZATION OF AN EXPERIMENTAL Januarv 1980
REFEREE BROADENED-SPECIFICATION (ERBS) 6. Performing Organization Code
AVIAnON TURBINE FUEL
7. Author(s) 8. Performing Organization Report No.
George M. Prok and Gary T. Seng E-206
10. Work Unit No.
9. Performing Organization Name and Address
National Aeronautics and Space Administration
11. Contract or Grant No.
Lewis Research Center
Cleveland, Ohio 44135 13. Type of Report and Period Covered
12. Sponsoring Agency Name and Address Technical Memorandum
National Aeronautics and Space Administration
14. Sponsoring Agency Code
Washington, D. C. 20546
15. Supplementary Notes
16. Abstract
Characterization data and a hydrocarbon compositional analysis are presented for a research
test fuel designated as an Experimental Referee Broadened-Specification (ERBS) aviation tur-
bine fuel. This research fuel, which is a special blend of kerosine and hydrotreated catalytic
gas oil, is a hypothetical representation of a future fuel should it become necessary to broaden
current kerojet specifications. It will be used as a reference fuel in research investigations
into the effects of fuel property variations on the performance and durability of jet aircraft
components, including combustors and fuel systems.
.
17. Key Words (Suggested by Author(s)) 18. Distribution StalemVlt
Fuels Unclassified - unlimited
Jet engines STAR Category 28
Combustion
19. Security Classi!. (of tt>is report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price.
Unc lassified Unclassified
• For sale by the National Technicallnf~rmation Service, Sprinefield. Virginia 22161
'-

National Aeronautics and SPECIAL FOURTH CLASS MAIL Postageand Fees Paid
Space Administration BOOK National Aeronautics andSpace Administration
Washington,D.C. NASA-451
20546
Official Business
Penalty for Private Use, $300
__A POSTMASTER: If Undeliverable (Section 158Postal Manual) Do Not Return


Initial characterization of an Experimental Referee Broadened-Specification (ERBS) aviation turbine fuel

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server