ASTM D7096-05
(Test Method)Standard Test Method for Determination of the Boiling Range Distribution of Gasoline by Wide-Bore Capillary Gas Chromatography
Standard Test Method for Determination of the Boiling Range Distribution of Gasoline by Wide-Bore Capillary Gas Chromatography
SIGNIFICANCE AND USE
The determination of the boiling range distribution of gasoline by gas chromatographic simulated distillation provides an insight into the composition of the components from which the gasoline has been blended. Knowledge of the boiling range distribution of gasoline blending components is useful for the control of refinery processes and for the blending of finished gasoline.
The determination of the boiling range distribution of light hydrocarbon mixtures by gas chromatographic simulated distillation has better precision than the conventional distillation by Test Method D 86. Additionally, this test method provides more accurate and detailed information about the composition of the light ends. The distillation data produced by this test method are similar to that which would be obtained from a cryogenic, true boiling point (15 theoretical plates) distillation.
SCOPE
1.1 This test method covers the determination of the boiling range distribution of gasoline and liquid gasoline blending components. It is applicable to petroleum products and fractions with a final boiling point of 280C (536F) or lower, as measured by this test method.
1.2 This test method is designed to measure the entire boiling range of gasoline and gasoline components with either high or low vapor pressure and is commonly referred to as Simulated Distillation (SimDis) by gas chromatographers.
1.3 This test method has been validated for gasoline containing ethanol. Gasolines containing other oxygenates are not specifically excluded, but they were not used in the development of this test method.
1.4 This test method can estimate the concentration of n-pentane and lighter saturated hydrocarbons in gasoline.
1.5 The values stated in SI units (degrees Celsius) are to be regarded as the standard. Results in degrees Fahrenheit can be obtained by simply substituting Fahrenheit boiling points in the calculation of the boiling point-retention time correlation.
1.6This 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 and health practices and determine the applicability of regulatory limitations prior to use.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation:D7096–05
Standard Test Method for
Determination of the Boiling Range Distribution of Gasoline
by Wide-Bore Capillary Gas Chromatography
This standard is issued under the fixed designation D7096; 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 D3700 Practice for Obtaining LPG Samples Using a Float-
ing Piston Cylinder
1.1 This test method covers the determination of the boiling
D4057 Practice for Manual Sampling of Petroleum and
range distribution of gasoline and liquid gasoline blending
Petroleum Products
components. It is applicable to petroleum products and frac-
D4307 Practice for Preparation of Liquid Blends for Use as
tions with a final boiling point of 280°C (536°F) or lower, as
Analytical Standards
measured by this test method.
D4626 Practice for Calculation of Gas Chromatographic
1.2 This test method is designed to measure the entire
Response Factors
boiling range of gasoline and gasoline components with either
D4814 Specification for Automotive Spark-Ignition Engine
high or low vapor pressure and is commonly referred to as
Fuel
Simulated Distillation (SimDis) by gas chromatographers.
D4815 Test Method for Determination of MTBE, ETBE,
1.3 This test method has been validated for gasoline con-
TAME, DIPE, tertiary-Amyl Alcohol and C to C Alco-
1 4
taining ethanol. Gasolines containing other oxygenates are not
hols in Gasoline by Gas Chromatography
specifically excluded, but they were not used in the develop-
D5191 Test Method for Vapor Pressure of Petroleum Prod-
ment of this test method.
ucts (Mini Method)
1.4 This test method can estimate the concentration of
D5599 Test Method for Determination of Oxygenates in
n-pentane and lighter saturated hydrocarbons in gasoline.
Gasoline by Gas Chromatography and Oxygen Selective
1.5 The values stated in SI units (degrees Celsius) are to be
Flame Ionization Detection
regarded as the standard. Results in degrees Fahrenheit can be
E594 Practice for Testing Flame Ionization Detectors Used
obtainedbysimplysubstitutingFahrenheitboilingpointsinthe
in Gas or Supercritical Fluid Chromatography
calculation of the boiling point-retention time correlation.
E1510 Practice for Installing Fused Silica Open Tubular
1.6 This standard does not purport to address all of the
Capillary Columns in Gas Chromatographs
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3. Terminology
priate safety and health practices and determine the applica-
3.1 Definitions:
bility of regulatory limitations prior to use.
3.1.1 area slice, n—area under a chromatogram within a
2. Referenced Documents specified retention time interval.
2 3.1.2 final boiling point (FBP), n—the point at which a
2.1 ASTM Standards:
cumulative volume count equal to 99.5 % of the total volume
D86 Test Method for Distillation of Petroleum Products at
counts under the chromatogram is obtained.
Atmospheric Pressure
3.1.3 initial boiling point (IBP), n—the point at which a
D2421 Practice for Interconversion of Analysis of C and
cumulative volume count equal to 0.5 % of the total volume
Lighter Hydrocarbons to Gas-Volume, Liquid-Volume, or
counts under the chromatogram is obtained.
Mass Basis
3.1.4 relative volume response factor (RVRF), n—the vol-
ume response factor (see 3.1.8) of a component i relative to the
This test method is under the jurisdiction of ASTM Committee D02 on
volume response factor of n-heptane.
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee
3.1.5 slice time, n—the retention time at the end of a given
D02.04 on Hydrocarbon Analysis.
area slice.
Current edition approved April 1, 2005. Published May 2005. DOI: 10.1520/
D7096-05.
3.1.6 slice width, n—the fixed duration (1 s, or less) of the
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
retention time intervals into which the chromatogram is di-
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
vided. It is determined from the reciprocal of the frequency
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. used in the acquisition of data.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D7096–05
TABLE 1 Typical Operating Conditions for Wide Bore
3.1.7 volume count, n—the product of a slice area (or an
Column Inlets
area under a peak) and a volume response factor.
Column length (m) 30 15
3.1.8 volume response factor, n—a constant of proportion-
Column I.D. (mm) 0.53 0.53
ality that relates the area under a chromatogram to liquid
Stationary phase 100 % poly- 100 % poly-
volume. dimethylsiloxane dimethylsiloxane
Film thickness (µm) 5 5
Carrier gas helium helium
4. Summary of Test Method
Carrier flow (mL/min) 20 15
Auxiliary flow (mL/min) 10 10
4.1 The sample is vaporized and transported by carrier gas
Column initial temperature (°C) 40 40
into a non-polar, wide-bore capillary gas chromatographic Initial time (min) 1 1
Program rate (°C/min) 25 20
column. The column temperature is raised at a reproducible,
Final temperature (°C) 265 230
linearratesoastoelutethehydrocarboncomponentsinboiling
Final hold (min) 4.00 2.50
point order for measurement by a flame ionization detector. Injection inlet purged-packed purged-packed
Sample introduction auto syringe injection auto syringe injection
Conditions are selected such that n-pentane and lighter satu-
Injector temperature (°C) 250 250
rated hydrocarbons in the calibration mixture are resolved
Detector temperature (°C) 280 300
discretely. Linear correlation between hydrocarbon boiling
Hydrogen flow (mL/min) 45 30
Air flow (mL/min) 450 300
point and retention time is established using a known mixture
Sample size (µL) 0.1 – 0.2 0.2
of hydrocarbons covering the boiling range expected in the
Area slice width (s) 0.5 – 0.2 0.5 – 0.2
sample. Area slices are converted to volume using theoretical Datarate(Hz) 2–5 2–5
hydrocarbon volume response factors. Oxygenated samples
require experimental determination of oxygenate response
TABLE 2 Typical Operating Conditions for Capillary Column Inlet
factors.
Column length (m) 30
Column I.D. (mm) 0.53
5. Significance and Use
Stationary phase 100 % polydimethylsiloxane
Film thickness 5 µm
5.1 The determination of the boiling range distribution of
Carrier gas helium (ramped flow)
gasoline by gas chromatographic simulated distillation pro-
Carrier flow (mL/min) 5mL/min (0.5 min) to 20mL/min @ 60mL/min
vides an insight into the composition of the components from Column initial temperature (°C) 40
Initial time (min) 1
whichthegasolinehasbeenblended.Knowledgeoftheboiling
Program rate (°C/min) 25
range distribution of gasoline blending components is useful
Final temperature (°C) 245
Final hold (min) 4
for the control of refinery processes and for the blending of
Injection port split
finished gasoline.
Sample introduction automatic syringe injection
5.2 The determination of the boiling range distribution of
Injector temperature (°C) 250
Detector temperature (°C) 250
light hydrocarbon mixtures by gas chromatographic simulated
Hydrogen flow (mL/min) 30
distillation has better precision than the conventional distilla-
Air flow (mL/min) 300
tion by Test Method D86. Additionally, this test method
Sample size (µL) 1 uL
Split ratio 1:50
provides more accurate and detailed information about the
Data rate 5 Hz
compositionofthelightends.Thedistillationdataproducedby
this test method are similar to that which would be obtained
from a cryogenic, true boiling point (15 theoretical plates)
7.1.1 Column Oven Temperature Programming—The gas
distillation.
chromatograph shall be capable of linear temperature-
programmed operation from –40 to 280°C at rates up to
6. Interferences
25°C/min.
6.1 Ethanol or other oxygenates may coelute with hydrocar-
7.1.2 Injection Port—The injection port shall be capable of
bonspresentinthesample.Sincetheresponseofoxygenatesis
operation at temperatures required to completely volatize and
substantially different from the response of hydrocarbons,
transfer the sample to the GC column. Non-splitting or
responsefactorsareusedtocorrecttheareaslicefortheelution
split/splitless vaporizing sample ports optimized for use with
interval of oxygenates.
wide-bore capillary columns are acceptable. If using a split
6.2 Concentrations of n-pentane and lighter saturated com-
inlet port, it should be designed to provide a linear sample split
pounds may be estimated from the analysis. However, early
injection.
eluting olefins present in the gasoline samples may coelute
7.1.3 Flame Ionization Detector—The detector shall be
with these compounds.
optimized for the use of wide-bore capillary gas chromato-
graphic columns and shall conform to the specifications as
7. Apparatus
described in Practice E594.
7.1 Gas Chromatograph—Any gas chromatograph (GC) 7.1.4 Carrier Gas Controls—The associated carrier gas
designed for use with wide-bore (0.53 mm inside diameter) controls shall be of sufficient precision to produce reproducible
capillarycolumns,thatmeetstheperformancecriteriaspecified column flows in order to maintain analytical integrity.
in Section 11, and has the following features may be used. 7.1.5 Baseline Correction—The gas chromatograph (or an-
Typical operating conditions are shown in Table 1. other component of the gas chromatographic system) shall be
D7096–05
capable of subtracting the area slice of a blank run from the quency of 2 to 5 Hz. The software should also be able to store
corresponding area slice of a sample run. This can be done the data for future recall, inspection, and analysis. The data
internally on some gas chromatographs (baseline compensa-
acquisitionsoftwareshouldbecapableofpresentingarealtime
tion)orexternallybysubtractingastored,digitizedsignalfrom
plot. It may also be capable of controlling the operating
a blank run.
variables of the gas chromatograph. Specialized software is
7.2 Sample Introduction—Sample introduction may be by
necessary to obtain the boiling point distribution.
meansofaconstantvolumeliquidsamplevalveorbyinjection
7.5 Bulk Sample Containers, floating piston cylinders (see
with a micro syringe through a septum. An automatic sample
9.1.1); epoxy phenolic-lined metal cans; glass bottles with
introduction device is essential to the reproducibility of the
polytetrafluoroethylene-lined screw caps.
analysis. Manual injections are not recommended. Poor injec-
tiontechniquecanresultinpoorresolution.Ifcolumnoverload
8. Reagents and Materials
occurs, peak skewing may result, leading to variation in
retention times.
8.1 Calibration Mixture—Asyntheticmixtureofpureliquid
7.2.1 Samples with a vapor pressure (VP) of less than 16
hydrocarbons with boiling points that encompass the boiling
psiaasmeasuredbyTestMethodD5191,orequivalent,maybe
range of the sample shall be used for retention time determi-
introducedintothegaschromatographbysyringeinjectioninto
nation and response factor validation. Response factors for
a heated, vaporizing inlet. Samples with vapor pressures
propane, isobutane, and n-butane are extrapolated from the
between 12 and 16 psia should be kept chilled (refrigerated or
relative molar response of the n-paraffins. An example of a
in a cooled sample tray) and may require injection with a
relative response factor mixture with suggested nominal com-
cooled syringe. Samples with a vapor pressure above 16 psia
position is given in Table 3. This mixture shall be accurately
should be introduced by way of a constant volume liquid
prepared on a mass basis using Practice D4307 or equivalent.
sampling valve. Refer to 9.1 for sampling practices.
8.1.1 Asinglecalibrationstandardmaybeusedforretention
7.3 Column—Any wide bore (0.53 mm inside diameter)
time-boilingpointdeterminationandresponsefactorvalidation
open tubular (capillary) column, coated with a non-polar
provided isopentane and heavier components are known quan-
(100 % polydimethylsiloxane) phase that meets the perfor-
titatively. Gaseous components propane, isobutane, and
mance criteria of 11.3 may be used. Columns of 15 to 30 metre
n-butaneareaddedinsmallquantities(<0.2vol%each).These
lengths with a stationary phase film thickness of 5.0 µm have
small quantities do not significantly change the concentrations
been successfully used. With either of these columns, initial
of the remaining hydrocarbons. This standard would also be
cryogenic temperatures are not necessary.
used for measuring performance criteria in Section 11.Itmay
7.4 Data Acquisition System—A computer provided with a
be practical to generate this standard by bubbling a small
monitor, printer, and data acquisition software is necessary to
amount of gaseous propane, isobutane, and n-butane
carry out this analysis. The computer should have sufficient
(Warning—Extremely flammable gases.) into a quantitative
hardware capacity and random access memory in order to run
the data acquisition program while acquiring data at a fre- mixture of isopentane and heavier components.
TABLE 3 Typical Calibration Mixture Composition and Properties of Hydrocarbons
A
A
Relative Density
BP
B C
Nominal Approx. FID
Compound 15.6/15.6°C
Mass% Vol% RVRF
°C °F
(60/60°F)
D
Propane -42.1 -43.8 0.5070 – – 1.394
D
Isobutane -11.8 10.8 0.5629 – – 1.241
D
n-Butane -0.5 31.1 0.5840 – – 1.196
Isopentane 27.8 82.1 0.6247 2.5 3.1 1.111
n-Pentane 36.1 96.9 0.6311 3.0 3.7 1.099
2-Methylpentane 60.3 140.5 0.6578 4.0 4.7 1.050
n-Hexane 68.9 155.7 0.6638 3.0 3.5 1.040
2,4-Dimethylpentane 80.5 176.9 0.6764 5.5 6.3 1.017
n-Heptane 99.2 209.2 0.6882 7.5 8.4 1.000
Toluene 110.6 231.1 0.8743 15.5 13.7 0.724
n-Octane 126.1 258.2 0.7070 7.0 7.6 0.971
p-Xylene 138.3 281.1 0.8666 16.0 14.2 0.736
n-Propylbenzene 159.2 318.6 0.8683 6.5 5.8 0.739
n-Decane 174.1 345.5 0.7342 4.5 4.7 0.932
n-Butylbenzene 183.3 361.9 0.8660 6.0 5.3 0.745
n-Dodecane 216.3 421.4 0.7527 3.5 3.6 0.907
n-Tridecane 235.5 455.8 0.7617 4.5 4.6 0.895
n-Tetradecane 253.6 488.4 0.7633 3.0 3.0 0.893
n-Pentadecane 271.1 519.2 0.7722 5.0 5.0 0.882
n-Hexadecane 287.2 548.3 0.7772 3.0 3.0 0.876
A
Normal boiling points and relative densities (15.6/15.6°C) obtained from Physical Constants of Hydrocarbon and Non-Hydrocarbon Compounds, ASTM Data Series
DS 4B, 1988.
B
Volume percent is calculated as mass percent divided by specific gravity, then normalized to 100 volume percent.
C
FID volume response factors, specified for use with this test method, are
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