ASTM D8267-24

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it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D8267 − 19a D8267 − 24
Standard Test Method for
Determination of Total Aromatic, Monoaromatic and
Diaromatic Content of Aviation Turbine Fuels Using Gas
Chromatography with Vacuum Ultraviolet Absorption
Spectroscopy Detection (GC-VUV)
This standard is issued under the fixed designation D8267; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This test method is a standard procedure for the determination of total aromatic, monoaromatic and diaromatic content in
aviation turbine fuels using gas chromatography and vacuum ultraviolet detection (GC-VUV).
1.2 Concentrations of compound classes and certain individual compounds are determined by percent mass or percent volume.
1.2.1 This test method is developed for testing aviation turbine engine fuels having concentration test results ranging from 0.487 %
to 27.876 % by volume total aromatic compounds, 0.49 % to 27.537 % by volume monoaromatics and 0.027 % to 2.523 % by
volume diaromatics.
NOTE 1—Samples with a final boiling point greater than 300 °C that contain triaromatics and higher polyaromatic compounds are not determined by this
test method.
1.3 Individual hydrocarbon components are not reported by this test method, however, any individual component determinations
are included in the appropriate summation of the total aromatic, monoaromatic or diaromatic groups.
1.3.1 Individual compound peaks are typically not baseline-separated by the procedure described in this test method, that is, some
components will coelute. The coelutions are resolved at the detector using VUV absorbance spectra and deconvolution algorithms.
1.4 This test method has been tested for aviation turbine engine fuels; this fuels including synthetic alternative jet fuels. This test
method may apply to other hydrocarbon streams boiling between hexane (68 °C) and heneicosane (356 °C), including sustainable
alternative jet fuels but has not been extensively tested for such applications.
1.5 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.04.0L on Gas Chromatography Methods.
Current edition approved Nov. 1, 2019March 15, 2024. Published November 2019April 2024. Originally approved in 2019. Last previous edition approved in 2019 as
D8267 – 19.D8267 – 19a. DOI: 10.1520/D8267-19A.10.1520/D8267-24.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D8267 − 24
1.7 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D1840 Test Method for Naphthalene Hydrocarbons in Aviation Turbine Fuels by Ultraviolet Spectrophotometry
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
D4307 Practice for Preparation of Liquid Blends for Use as Analytical Standards
D5186 Test Method for Determination of the Aromatic Content and Polynuclear Aromatic Content of Diesel Fuels By
Supercritical Fluid Chromatography
D6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measure-
ment System Performance
D6300 Practice for Determination of Precision and Bias Data for Use in Test Methods for Petroleum Products, Liquid Fuels, and
Lubricants
D6379 Test Method for Determination of Aromatic Hydrocarbon Types in Aviation Fuels and Petroleum Distillates—High
Performance Liquid Chromatography Method with Refractive Index Detection
D6730 Test Method for Determination of Individual Components in Spark Ignition Engine Fuels by 100-Metre Capillary (with
Precolumn) High-Resolution Gas Chromatography
D6792 Practice for Quality Management Systems in Petroleum Products, Liquid Fuels, and Lubricants Testing Laboratories
D7372 Guide for Analysis and Interpretation of Proficiency Test Program Results
3. Terminology
3.1 Definitions:
3.1.1 For definitions of terms used in this test method, refer to Terminology D4175.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 diaromatics, n—hydrocarbon compounds containing two aromatic rings; this group includes naphthalene, biphenyls,
acenaphthene, acenaphthylene and alkylated derivatives of these hydrocarbons.
3.2.1.1 Discussion—
Aviation turbine fuel specifications limit naphthalenes which includes naphthalene, acenaphthene, and alkylated derivatives of
these hydrocarbons. The Test Method D1840 method for naphthalenes states that biphenyls interfere with the analysis. Biphenyls
if present in typical aviation turbine fuel would be measured as naphthalenes in Test Method D1840, therefore the terms
naphthalenes and diaromatics can be considered synonymous in the context of this test method.
3.2.2 integration filter, n—a mathematical operation performed on an absorbance spectrum for the purpose of converting the
spectrum to a single-valued response suitable for representation in a two-dimensional chromatogram plot.
3.2.3 library reference spectrum, n—an absorbance spectrum representation of a molecular species stored in a library database and
used for identification of a compound/compound class or deconvolution of multiple coeluting compounds.
3.2.4 monoaromatic hydrocarbons, n—hydrocarbon compounds containing one aromatic ring; including benzene, alkylsubstituted
benzenes, indans, tetralins, alkyl-substituted indans, and alkyl-substituted tetralins.
3.2.5 response area, n—generally refers to a response summed over a given time interval and has units of absorbance units (AU).
3.2.5.1 Discussion—
A time factor necessary to convert a response area to a true mathematical area cancels out of all critical calculations and is omitted.
3.3 Abbreviations:
3.3.1 AU—absorbance units
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
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3.3.2 GC-VUV—gas chromatography with vacuum ultraviolet spectroscopy detection
3.3.3 RI—retention index
3.3.4 RRF—relative response factor
4. Summary of Test Method
4.1 An aviation turbine fuel sample is introduced to a gas chromatographic (GC) system. After volatilization, the effluent is
introduced onto a GC column for separation, and then detected by a vacuum ultraviolet absorption spectroscopy detector. The
separation is accomplished using a 30 m, nonpolar phase capillary column and a moderately fast temperature ramp (typical
operating parameters of this test method are given in Table 1). Coelutions are resolved by the detector using vacuum ultraviolet
absorbance spectra and deconvolution.
4.2 The calculation of the results is based on the determination of the total response areas of each of the classes of saturate,
aromatic and diaromatic compounds. The saturates class includes the summation of the paraffins, isoparaffins, and naphthenes. The
total aromatics class includes the summation of monoaromatics and diaromatics. The percent mass concentrations are calculated
from the response areas using class-based relative response factors, as appropriate. The volume percent concentrations are
calculated from the mass concentrations by applying specific component or class-based density values as appropriate.
5. Significance and Use
5.1 The determination of class group composition of aviation turbine fuels is useful for evaluating quality and expected
performance, as well as compliance with various industry specifications and governmental regulations.
6. Interferences
6.1 Interferences with this test method, if any, have not been determined.
TABLE 1 Typical Instrument Settings for GC-VUV Aviation
Turbine Fuel Measurement
Capillary, 30 m × 0.25 mm ID ×
Column Dimensions
0.25 μm film thickness
A
Column phase Nonpolar (for example, 100 %
dimethyl polysiloxane)
Injector temperature 250 °C
B
Injection volume 1.0 μL
B
Split ratio 100:1
Column flow (constant flow mode) 2.0 mL/min
Oven initial temperature 50 °C
Initial hold time 0.1 min
Oven ramp 15 °C/min
Final oven temperature 260 °C
Final hold time 0 min
Detector makeup gas pressure as per manufacturer’s instructions
(gauge)
Data scan rate 7.0 Hz
Detector flow cell temperature 275 °C
Transfer line temperature 275 °C
A
Columns with low bleed phases such as MS grade have been successfully used
for this application (see 11.6).
B
Other injection volumes and split ratios may be used to achieve the required
naphthalene response (see 13.2).
The sole source of supply of the apparatus known to the committee at this time is VUV-Analytics, Cedar Park, Texas. If you are aware of alternative suppliers, please
provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, which
you may attend.
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7. Apparatus
7.1 Gas Chromatograph, equipped with automated oven temperature control and split/splitless inlet.
7.1.1 Flow Controllers—The gas chromatograph must be equipped with mass flow controllers capable of maintaining carrier gas
flow constant to 61 % over the full operating temperature range of the column. The inlet pressure of the carrier gas supplied to
the gas chromatograph must be at least 485 kPa. This will ensure that the minimum pressure needed to compensate for the increase
in column back-pressure as the column temperature is maintained.
7.1.2 It is highly recommended that the gas chromatograph is equipped with an autosampler. All statistical data were obtained
using a GC equipped with an autosampler.
7.2 Carrier Gas, for gas chromatograph: helium (see 8.2).
7.3 Purge/Makeup Gas, for detector: helium, nitrogen, or argon (see 8.3).
7.4 Oxygen, Water, Hydrocarbon Filters, to further purify GC carrier gas and detector purge/makeup gas.
7.5 Capillary Analytical Column, nonpolar (for example, dimethyl polysiloxane) phase, dimensions 30 m length, 0.25 mm internal
diameter, 0.25 μm film thickness.
7.6 Vacuum Ultraviolet Absorption Spectroscopy Detector, capable of measuring 125 nm to 240 nm absorbance spectra with a
wavelength resolution of 1 nm or better.
7.6.1 The detector shall be able to interface with a gas chromatographic system and measure an eluent with a scan frequency of
at least 5 Hz with a baseline peak-to-peak noise width over a 10 s interval no greater than 0.002 AU when averaged over the
following wavelength regions: 125 nm to 240 nm, 170 nm to 200 nm, 125 nm to 160 nm, and 0.001 AU when averaged over the
140 nm to 160 nm wavelength region.
7.6.2 The detector shall be equipped with a shutter or equivalent mechanism that allows the detector array to be blocked from the
light source in order to perform a “dark” measurement of electronic noise level.
7.6.3 The detector shall be equipped with a flow cell capable of being heated to at least 275 °C.
7.6.4 The detector shall have an independently controlled makeup gas capability, capable of providing up to 5 mL ⁄min additional
flow of nitrogen, helium, or argon to the flow cell.
7.7 Data Processing System, capable of storing and processing absorbance scan data and corresponding time.
7.7.1 Data processing system shall include a database library of vacuum ultraviolet reference spectra, compound class information,
carbon number, density, and approximate retention index values. Data processing system shall also store relative response factors
for each hydrocarbon class in addition to relative response factors for individually reported compounds.
7.7.2 Data processing system shall be capable of implementing equations and fit procedures that result in deconvolution of
absorbance spectra that contain contributions from multiple species.
7.7.3 Data processing system shall be capable of binning and storing response contributions from each deconvolution analysis and
reporting a combined total response at the end of the analysis.
7.7.4 Data processing system shall be capable of implementing equations to convert response areas to percent mass and further
convert percent mass to percent volume.
8. Reagents and Materials
8.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all
reagents shall conform to the specifications of the committee on Analytical Reagents of the American Chemical Society where such
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specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity
to permit its use without lessening the accuracy of the determination.
8.2 Helium carrier gas for gas chromatograph, 99.999 % pure.
8.3 Nitrogen, helium, or argon purge/makeup gas for vacuum ultraviolet detector, 99.999 % pure.
8.4 Methylene chloride, reagent grade, used as a solvent test sample and GC rinse solvent. (Warning—Toxic material. May be
combustible at high temperatures.)
8.5 A system validation mixture that complies with Practice D4307, having the components and approximate concentrations given
in Table 2. The concentrations of the prepared system validation mixture should be close to those in Table 2 and shall otherwise
be accurately known.
8.5.1 The components of the system validation mixture may be modified to include other components of particular relevance to
this test method.
8.5.2 The components of the system validation mixture must include linear alkanes in a continuous series from C6 to C21 at the
nominal concentrations in Table 2.
8.5.2.1 The system validation mixture is used to determine a retention time marker list (see 12.1 and 12.2).
8.5.2.2 The system validation mixture is used to determine splitter linearity (see 13.3.2).
8.6 A quality control (QC) sample, similar in characteristics to samples that are to be routinely analyzed such as aviation turbine
engine fuel. See Section 18 on Quality Control Monitoring.
9. Hazards
9.1 Many of the compounds in aviation turbine engine fuel or other test samples used in this test method are toxic, flammable,
or both. Safety and sample-handling procedures appropriate for working with such materials shall be in place before attempting
to use this test method.
TABLE 2 System Validation Mixture
Component Concentration (percent mass)
Hexane 0.25
Heptane 0.25
Octane 0.25
Nonane 0.25
Decane 0.25
Undecane 0.25
Dodecane 0.25
Tridecane 0.25
Tetradecane 0.25
Pentadecane 0.25
Hexadecane 0.25
Heptadecane 0.25
Octadecane 0.25
Nonadecane 0.25
Eicosane 0.25
Heneicosane 0.25
Naphthalene 0.25
2-Methylnaphthalene 0.25
1,2,4-Trimethylbenzene 0.25
Methylene Chloride Balance
Reagent Chemicals, American Chemical Society Specifications,ACS Reagent Chemicals, Specifications and Procedures for Reagents and Standard-Grade Reference
Materials, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed by the American Chemical Society, see Analar Standards for
Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC),
Rockville, MD.
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10. Sampling
10.1 Refer to Practice D4057 for guidelines on obtaining aviation turbine engine fuel samples for analysis.
11. Preparation of Apparatus
11.1 Ensure that all gas connections are properly made, without leaks.
11.2 Install oxygen, moisture, and hydrocarbon filters in gas lines upstream of GC and detector. Maintain gas filters as instructed
by manufacturer.
11.3 Install the 30 m column in the GC inlet. Condition the column according to the column manufacturer’s recommendations
prior to installation in the detector.
11.4 Perform maintenance on the GC as suggested by manufacturer, such as replacing septum and liner.
11.5 Configure the injector, carrier gas, and other GC parameters according to Table 1.
11.6 Inject the solvent test sample defined in 8.4 and run the GC-VUV apparatus through a full oven ramp and cool-down cycle.
Repeat.
11.6.1 Assess the baseline on either a solvent test sample or a system validation mixture (see 8.5) run. The average absorbance
value (125 nm to 240 nm) of at least a 0.1 min section of the baseline near the end of the oven ramp shall be no more than
60.0035 AU of the average value (125 nm to 240 nm) of the initial 0.5 min to 1.0 min range.
12. Calibration and Standardization
12.1 On installation of GC-VUV apparatus, after significant maintenance of GC-VUV apparatus, or after a significant method
change, establish a retention index file. Run the system validation mixture (see 8.5) using the same flow conditions and oven ramp
profile as measured samples (see Table 1 for recommended run conditions). Record the retention times of C6 through C21 linear
alkanes. These will serve as retention time markers.
12.1.1 Significant method changes include changing the GC, column type, make-up gas pressure, or oven ramp profile. Significant
maintenance of the GC-VUV apparatus includes changing or trimming the analytical column.
12.2 A list of retention times and retention indices for the linear alkanes is used to estimate elution times of other compounds in
the VUV library according to an interpolation scheme. The retention index scheme sets the linear alkane retention indices to
multiples of 100 according to carbon number: nonane RI = 900, decane RI = 1000, etc.
12.2.1 Once updated, the same retention time marker list is used for all subsequent aviation turbine fuel measurements until the
next modification or maintenance of the GC-VUV instrumentation.
12.3 The conversion from response areas to percent mass uses class-based relative response factors. The relative response factors
account for the differing areal response per unit mass for the various hydrocarbon classes.
12.4 For the purpose of this calculation, the response at a given elution time refers to the absorbance averaged over the 125 nm
to 240 nm wavelength region. The response area refers to the sum of the response over all detector scans within a given time
region. A true area can be generated by multiplying this quantity by the time interval between scans. However, this step is
unnecessary when the scan rate is kept constant throughout a given measurement. For the purposes of this test method, the response
area is taken to be a sum having units of absorbance units.
12.5 The response factors are relative to the response of methane, which is taken to have a relative response factor of 1.
12.6 Relative response factors used to obtain the precision data in this test method are given in Table 3 and Table 4, and are
suitable for use with this test method.
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TABLE 3 Relative Response Factors for Bulk Hydrocarbon
Classes
Relative Response Factor
Hydrocarbon Class
A
C6 to C21
Saturates 0.811 to 0.683
Monoaromatics 0.258 to 0.422
Diaromatics 0.198 to 0.213
A
A compound’s relative response factor is a function of the type and number of
chemical bonds.
TABLE 4 Relative Response Factors for Specific Individual
Compounds and Compound Groups
Compound Relative Response Factor
Benzene 0.258
Toluene 0.267
Ethylbenzene 0.284
Xylenes 0.284
1,2,4-trimethylbenzene 0.279
Naphthalene 0.198
Methylnaphthalenes 0.202
12.7 Relative response factors may alternatively be refined or determined as described in Appendix X2X1.
13. Pre-Measurement Validation
13.1 Before proceeding with measurements or after a significant change or maintenance of the GC-VUV system, the procedures
in Section 11 should have been completed, and a retention index file generated or verified following the procedure in 12.1 and 12.2.
13.2 Verify that the total response for naphthalene is 3.2560.25 in the system validation mixture (see 8.5).
13.2.1 Otherwise adjust the detector make-up gas pressure in 0.14 kPa increments and reanalyze the system validation mixture,
checking the naphthalene response until it is in the specified range. Increasing the detector make-up gas pressure will decrease the
naphthalene response.
13.2.2 If the detector make-up gas pressure has been changed, reanalyze the retention index sample (see 12.1 and 12.2) and
establish a new retention index file. Adjusting the detector make-up gas pressure will change retention times. Reanalyze the system
validation mixture (see 8.5) and verify the total response for naphthalene (see 13.2).
13.3 The system validation mixture (see 8.5) serves as a verification of the analytical system.
13.3.1 System Accuracy—The system validation mixture percent by mass results for individual paraffins, aromatics, and
diaromatics shall be within 610 % relative of the certified concentration values.
13.3.2 Split Linearity—The experimentally determined percent by mass ratio of C21 to C7 shall be within 10 % relative of the ratio
of the certified percent by mass in the system validation mixture.
13.3.2.1 If the split linearity results are unacceptable, verify that the inlet seals, liner, and column position are designed to
minimize split inlet mass discrimination. A GC inlet liner packed with deactivated glass wool is recommended.
13.4 Analyze the quality control sample defined in 8.6.
13.5 If the specifications in 13.3 or control limits in 13.4 are not met, verify the functionality of all GC-VUV components, validity
of retention time marker list, and validity/quality of the QC or system validation mixture, or both. Repeat setup methodology in
Sections 11, 12, and 13 as necessary to ensure specifications in 13.3 and 13.4 are met before proceeding.
13.6 It is strongly recommended that the system validation mixture and or the QC sample be run with every subsequent batch of
20 samples.
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14. Procedure
14.1 Inject the sample into the GC injector port. Typical GC method and detector conditions are given in Table 1.
14.2 The system shall record a dark scan immediately after start.
14.3 The system shall record a reference scan immediately after the dark scan.
14.3.1 The reference scan refers to an initial detector scan used as a reference to convert subsequent detector scans to absorbance
scans, and is defined in Annex A1. It is not a library reference spectrum.
14.4 The system shall record 125 nm to 240 nm absorbance spectra and time of scan for each detector scan. Conversion of
recorded intensity data to absorbance is given in Annex A1.
14.5 At the end of the GC run, the data collection shall automatically stop, and the recorded absorbance spectra processed in order
to obtain response areas for each of the hydrocarbon classes and individual compounds being monitored.
14.5.1 Calculate percent mass for each hydrocarbon group; saturates, aromatics, and diaromatics.
14.5.2 Calculate percent volume results from the percent mass results and class/compound densities.
15. Calculation
NOTE 2—See pertinent information on modeling absorbance data in Annex A2.
15.1 Divide the measured chromatogram into time slices of a given width, ∆t. Define the following parameters:
15.1.1 A retention index (RI) window,
15.1.2 A chi-squared iteration threshold, expressed as a percentage,
15.1.3 An R threshold,
15.1.4 A saturation threshold, and
15.1.5 An initial background time region (optional).
15.2 If an initial background time region is defined, calculate a background spectrum from the average of the absorbance scans
over the background time region.
15.3 Analyze each time slice using the following algorithm:
15.3.1 Calculate the total absorbance from the sum of the absorbance scans within the time slice.
15.3.1.1 If a background spectrum is defined, subtract the background spectrum from each of the individual absorbance spectra
within the time slice. Sum the resulting background-subtracted spectra to obtain the total absorbance spectrum for the time slice.
15.3.1.2 If the absorbance value at a given wavelength exceeds the saturation threshold for any of the absorbance scans within
the time slice, remove the data at that wavelength value from the total absorbance and library reference spectra used in subsequent
fits for that time slice.
15.3.2 Calculate the average retention index of the time slice using the average elution time of the time slice and the list of
retention time markers. A linear interpolation scheme is sufficient.
15.3.3 Construct a list consisting of all compounds in the VUV reference library within 6RI window of the average retention
index of the time slice.
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15.3.4 Perform a tiered search on the total absorbance spectrum, dra
...