ASTM D6733-01(2020)

Standard Test Method for Determination of Individual Components in Spark Ignition Engine Fuels by 50-Metre Capillary High Resolution Gas Chromatography

SIGNIFICANCE AND USE
5.1 Knowledge of the individual component composition (speciation) of gasoline fuels and blending stocks is useful for refinery quality control and product specification. Process control and product specification compliance for many individual hydrocarbons may be determined through the use of this test method.
SCOPE
1.1 This test method covers the determination of individual hydrocarbon components of spark-ignition engine fuels with boiling ranges up to 225 °C. Other light liquid hydrocarbon mixtures typically encountered in petroleum refining operations, such as, blending stocks (naphthas, reformates, alkylates, and so forth) may also be analyzed; however, statistical data was obtained only with blended spark-ignition engine fuels. The tables in Annex A1 enumerate the components reported. Component concentrations are determined in the range from 0.10 % to 15 % by mass. The procedure may be applicable to higher and lower concentrations for the individual components; however, the user must verify the accuracy if the procedures are used for components with concentrations outside the specified ranges.  
1.2 This test method is applicable also to spark-ignition engine fuel blends containing oxygenated components. However, in this case, the oxygenate content must be determined by Test Methods D5599 or D4815.  
1.3 Benzene co-elutes with 1-methylcyclopentene. Benzene content must be determined by Test Method D3606 or D5580.  
1.4 Toluene co-elutes with 2,3,3-trimethylpentane. Toluene content must be determined by Test Method D3606 or D5580.  
1.5 Although a majority of the individual hydrocarbons present are determined, some co-elution of compounds is encountered. If this procedure is utilized to estimate bulk hydrocarbon group-type composition (PONA) the user of such data should be cautioned that error may be encountered due to co-elution and a lack of identification of all components present. Samples containing significant amounts of naphthenic (for example, virgin naphthas) constituents above n-octane may reflect significant errors in PONA type groupings. Based on the interlaboratory cooperative study, this procedure is applicable to samples having concentrations of olefins less than 20 % by mass. However, significant interfering coelution with the olefins above C7 is possible, particularly if blending components or their higher boiling cuts such as those derived from fluid catalytic cracking (FCC) are analyzed, and the total olefin content may not be accurate. Many of the olefins in spark ignition fuels are at a concentration below 0.10 %; they are not reported by this test method and may bias the total olefin results low.  
1.5.1 Total olefins in the samples may be obtained or confirmed, or both, by Test Method D1319 (volume %) or other test methods, such as those based on multidimensional PONA type of instruments.  
1.6 If water is or is suspected of being present, its concentration may be determined, if desired, by the use of Test Method D1744. Other compounds containing sulfur, nitrogen, and so forth, may also be present, and may co-elute with the hydrocarbons. If determination of these specific compounds is required, it is recommended that test methods for these specific materials be used, such as Test Method D5623 for sulfur compounds.  
1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.  
1.8 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.  
1.9 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...

General Information

• Status: Published
• Publication Date: 31-Oct-2020
• ICS: 71.040.50 - Physicochemical methods of analysis
• ICS: 75.160.20 - Liquid fuels
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.04.0L - Gas Chromatography Methods

Relations

• Refers: ASTM D5623-24 - Standard Test Method for Sulfur Compounds in Light Petroleum Liquids by Gas Chromatography and Sulfur Selective Detection
• Effective Date: 01-Mar-2024
• Refers: ASTM D3606-24 - Standard Test Method for Determination of Benzene and Toluene in Spark Ignition Fuels by Gas Chromatography
• Effective Date: 01-Mar-2024
• Refers: ASTM D5599-17 - Standard Test Method for Determination of Oxygenates in Gasoline by Gas Chromatography and Oxygen Selective Flame Ionization Detection
• Effective Date: 01-May-2017
• Refers: ASTM D5599-15 - Standard Test Method for Determination of Oxygenates in Gasoline by Gas Chromatography and Oxygen Selective Flame Ionization Detection
• Effective Date: 01-Jun-2015
• Refers: ASTM D1319-14 - Standard Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorption
• Effective Date: 01-Oct-2014
• Refers: ASTM D5623-94(2014) - Standard Test Method for Sulfur Compounds in Light Petroleum Liquids by Gas Chromatography and Sulfur Selective Detection
• Effective Date: 15-Jan-2014
• Refers: ASTM D1744-13 - Standard Test Method for Determination of Water in Liquid Petroleum Products by Karl Fischer Reagent (Withdrawn 2016)
• Effective Date: 01-Dec-2013
• Refers: ASTM D1319-13 - Standard Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorption
• Effective Date: 01-May-2013
• Refers: ASTM D4057-06(2011) - Standard Practice for Manual Sampling of Petroleum and Petroleum Products
• Effective Date: 01-Jun-2011
• Refers: ASTM D3606-10 - Standard Test Method for Determination of Benzene and Toluene in Finished Motor and Aviation Gasoline by Gas Chromatography
• Effective Date: 01-Oct-2010
• Refers: ASTM D3606-10e1 - Standard Test Method for Determination of Benzene and Toluene in Finished Motor and Aviation Gasoline by Gas Chromatography
• Effective Date: 01-Oct-2010
• Refers: ASTM D5599-00(2010) - Standard Test Method for Determination of Oxygenates in Gasoline by Gas Chromatography and Oxygen Selective Flame Ionization Detection
• Effective Date: 01-Oct-2010
• Refers: ASTM D4815-09 - Standard Test Method for Determination of MTBE, ETBE, TAME, DIPE, tertiary-Amyl Alcohol and C₁ to C₄ Alcohols in Gasoline by Gas Chromatography
• Effective Date: 01-Oct-2009
• Refers: ASTM D5623-94(2009) - Standard Test Method for Sulfur Compounds in Light Petroleum Liquids by Gas Chromatography and Sulfur Selective Detection
• Effective Date: 15-Apr-2009
• Refers: ASTM D1319-08 - Standard Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorption
• Effective Date: 15-Oct-2008

Overview

ASTM D6733-01(2020) is the international standard test method for the determination of individual components in spark ignition engine fuels using 50-metre capillary high resolution gas chromatography. Developed by ASTM International, this standard provides procedures for analyzing the detailed hydrocarbon composition (speciation) of gasoline and related light liquid petroleum products. Its application is essential for refinery quality control, regulatory compliance, and supporting accurate fuel formulation.

The method is designed for spark ignition engine fuels with boiling points up to 225 °C, including unleaded gasoline and various petroleum blending stocks such as naphthas, reformates, and alkylates. By separating and quantifying individual hydrocarbons, this test method enables precise monitoring of fuel characteristics, ensuring both product quality and adherence to environmental and safety standards.

Key Topics

• Detailed Hydrocarbon Analysis (DHA): The standard provides a robust process for speciation of gasoline and light hydrocarbons, identifying and quantifying individual components typically found in spark ignition fuel blends.
• High-Resolution Gas Chromatography: Utilizes a 50-metre capillary column for effective separation and quantitative analysis of fuel components.
• Component Concentration Range: Detects and quantifies hydrocarbons from 0.10% to 15% by mass, with procedures available for other concentration ranges upon verification.
• Blended and Oxygenated Fuels: While broadly applicable, for samples containing oxygenates, additional ASTM test methods (D5599 or D4815) are referenced to quantify those components.
• Co-Elution and Analytical Limits: Some hydrocarbons can co-elute in chromatography (e.g., benzene with 1-methylcyclopentene, toluene with 2,3,3-trimethylpentane), requiring auxiliary methods (ASTM D3606, D5580, etc.) for precise quantification.
• Olefin Analysis and PONA Grouping: Provides detailed data on paraffins, olefins, naphthenes, and aromatics (PONA), but notes potential errors if co-elution occurs or for samples high in naphthenic constituents.
• Supporting Quality and Regulatory Compliance: The method underpins refinery process control and aids in confirming that products meet regulatory and commercial specifications.

Applications

This standard test method is widely used in the following practical applications:

• Refinery Quality Control: Enables refineries to monitor the composition of gasoline and blending stocks, facilitating consistent product quality and process optimization.
• Product Specification Compliance: Assists fuel producers and marketers in verifying that fuels meet specified regulatory and commercial requirements regarding individual hydrocarbon content.
• Research and Development: Supports engine and fuel researchers with precise compositional data for developing advanced fuels or optimizing blending recipes.
• Environmental and Safety Assessments: Permits reliable identification of individual hydrocarbons, supporting environmental impact studies and compliance with emissions standards.
• Forensic and Regulatory Testing: Assists laboratories examining samples for compliance with government-mandated fuel standards.

Related Standards

For complementary testing or when analytical limitations arise, the following ASTM standards are closely related to ASTM D6733-01(2020):

• D1319: Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorption
• D3606 / D5580: Test Methods for Precise Benzene and Toluene Determination in Spark Ignition Fuels
• D5599 / D4815: Test Methods for Oxygenates in Gasoline
• D5623: Test Method for Sulfur Compounds in Light Petroleum Liquids
• E355: Practice for Gas Chromatography Terms and Relationships

By following ASTM D6733-01(2020), laboratories and refineries can ensure the accurate, reproducible, and comparable analysis of gasoline and related fuels using advanced capillary gas chromatography techniques, supporting better quality control and compliance in the fuel industry.

Standards Content (Sample)

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.
Designation: D6733 − 01 (Reapproved 2020)
Standard Test Method for
Determination of Individual Components in Spark Ignition
Engine Fuels by 50-Metre Capillary High Resolution Gas
Chromatography
This standard is issued under the fixed designation D6733; 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 may reflect significant errors in PONA type groupings. Based
on the interlaboratory cooperative study, this procedure is
1.1 This test method covers the determination of individual
applicabletosampleshavingconcentrationsofolefinslessthan
hydrocarbon components of spark-ignition engine fuels with
20 % by mass. However, significant interfering coelution with
boiling ranges up to 225 °C. Other light liquid hydrocarbon
the olefins above C is possible, particularly if blending
mixtures typically encountered in petroleum refining
components or their higher boiling cuts such as those derived
operations, such as, blending stocks (naphthas, reformates,
from fluid catalytic cracking (FCC) are analyzed, and the total
alkylates, and so forth) may also be analyzed; however,
olefincontentmaynotbeaccurate.Manyoftheolefinsinspark
statistical data was obtained only with blended spark-ignition
ignition fuels are at a concentration below 0.10 %; they are not
engine fuels. The tables in Annex A1 enumerate the compo-
reported by this test method and may bias the total olefin
nents reported. Component concentrations are determined in
results low.
the range from 0.10 % to 15 % by mass.The procedure may be
1.5.1 Total olefins in the samples may be obtained or
applicabletohigherandlowerconcentrationsfortheindividual
confirmed, or both, by Test Method D1319 (volume %) or
components; however, the user must verify the accuracy if the
other test methods, such as those based on multidimensional
procedures are used for components with concentrations out-
PONA type of instruments.
side the specified ranges.
1.2 This test method is applicable also to spark-ignition
1.6 If water is or is suspected of being present, its concen-
engine fuel blends containing oxygenated components.
tration may be determined, if desired, by the use of Test
However, in this case, the oxygenate content must be deter-
Method D1744. Other compounds containing sulfur, nitrogen,
mined by Test Methods D5599 or D4815.
and so forth, may also be present, and may co-elute with the
hydrocarbons. If determination of these specific compounds is
1.3 Benzene co-elutes with 1-methylcyclopentene. Benzene
required, it is recommended that test methods for these specific
content must be determined by Test Method D3606 or D5580.
materials be used, such as Test Method D5623 for sulfur
1.4 Toluene co-elutes with 2,3,3-trimethylpentane. Toluene
compounds.
content must be determined by Test Method D3606 or D5580.
1.7 The values stated in SI units are to be regarded as the
1.5 Although a majority of the individual hydrocarbons
standard. The values given in parentheses are provided for
present are determined, some co-elution of compounds is
information only.
encountered. If this procedure is utilized to estimate bulk
hydrocarbon group-type composition (PONA) the user of such
1.8 This standard does not purport to address all of the
data should be cautioned that error may be encountered due to
safety concerns, if any, associated with its use. It is the
co-elution and a lack of identification of all components
responsibility of the user of this standard to establish appro-
present. Samples containing significant amounts of naphthenic
priate safety, health, and environmental practices and deter-
(for example, virgin naphthas) constituents above n-octane
mine the applicability of regulatory limitations prior to use.
1.9 This international standard was developed in accor-
dance with internationally recognized principles on standard-
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricantsand is the direct responsibility of
ization established in the Decision on Principles for the
Subcommittee D02.04.0L on Gas Chromatography Methods.
Development of International Standards, Guides and Recom-
Current edition approved Nov. 1, 2020. Published November 2020. Originally
mendations issued by the World Trade Organization Technical
approved in 2001. Last previous edition approved in 2016 as D6733 – 01 (2016).
DOI: 10.1520/D6733-01R20. Barriers to Trade (TBT) Committee.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6733 − 01 (2020)
2. Referenced Documents 5. Significance and Use
2.1 ASTM Standards: 5.1 Knowledge of the individual component composition
D1319 Test Method for Hydrocarbon Types in Liquid Petro- (speciation) of gasoline fuels and blending stocks is useful for
leum Products by Fluorescent Indicator Adsorption refinery quality control and product specification. Process
D1744 Test Method for Determination of Water in Liquid control and product specification compliance for many indi-
Petroleum Products by Karl Fischer Reagent (Withdrawn vidual hydrocarbons may be determined through the use of this
2016) test method.
D3606 Test Method for Determination of Benzene and
6. Apparatus
Toluene in Spark Ignition Fuels by Gas Chromatography
6.1 Instrumentation—A gas chromatograph capable of op-
D4057 Practice for Manual Sampling of Petroleum and
erating under the conditions outlined in Table 1, equipped with
Petroleum Products
a split injector, a carrier gas pressure control, and a flame
D4420 Test Method for Determination of Aromatics in
ionization detector which are required.
Finished Gasoline by Gas Chromatography (Withdrawn
2004)
6.2 Sample Introduction System—Manual or automatic liq-
D4815 Test Method for Determination of MTBE, ETBE,
uid syringe sample injection may be employed.
TAME, DIPE, tertiary-Amyl Alcohol and C to C Alco-
1 4
6.3 Data Acquisition System—Any data system can be used
hols in Gasoline by Gas Chromatography
with a requirement:
D5580 Test Method for Determination of Benzene, Toluene,
6.3.1 Sampling rate of 10 Hz or more with a storage of
Ethylbenzene, p/m-Xylene, o-Xylene, C and Heavier
sampling data for later processing.
Aromatics, and Total Aromatics in Finished Gasoline by
6.3.2 Capacity for at least 400 peaks/analysis.
Gas Chromatography
6.3.3 Identification of individual components from retention
D5599 Test Method for Determination of Oxygenates in
time; software can be used to automatically identify the peaks
Gasoline by Gas Chromatography and Oxygen Selective
with the index system determined from Table A1.1 or Table
Flame Ionization Detection
A1.2.
D5623 Test Method for Sulfur Compounds in Light Petro-
leum Liquids by Gas Chromatography and Sulfur Selec- 6.4 Sampling—Two millilitres or more crimp-top vials and
tive Detection aluminum caps with polytetrafluoroethylene (PTFE)-lined
E355 Practice for Gas Chromatography Terms and Relation- septa are used to transfer the sample.
ships
6.5 Capillary Column—A 50 m fused silica capillary col-
umn with an internal diameter of 0.2 mm, containing a 0.5 µm
3. Terminology
film thickness of bonded dimethylpolysiloxane phase is used.
3.1 Definitions—This test method makes reference to many
The features must be respected to reproduce the separation of
common gas chromatographic procedures, terms, and relation-
the reference chromatogram. The column must meet the
ships. Detailed definitions can be found in Practice E355.
criteria of efficiency, resolution, and polarity defined in Section
10.
4. Summary of Test Method
7. Reagents and Materials
4.1 Representative samples of the petroleum liquid are
introduced into a gas chromatograph equipped with an open
7.1 Carrier Gas and Make-up, helium, 99.99 mol % pure.
tubular (capillary) column coated with specified stationary
(Warning—Compressed gas under high pressure.)
phase(s). Helium carrier gas transports the vaporized sample
7.2 Fuel Gas, hydrogen, hydrocarbon free, 99.99 mol %
through the column in which it is partitioned into individual
pure. (Warning—Compressed gas under high pressure. Ex-
components, which are sensed with a flame ionization detector
tremely flammable.)
as they elute from the end of the column. The detector signal
is recorded digitally by way of an integrator or integrating
TABLE 1 Operating Conditions
computer. Each eluting component is identified by comparing
Temperatures Method 1 Method 2
its retention time to those established by analyzing reference
Column initial isotherm, °C 35 10
standards or samples under identical conditions. The concen-
Initial hold time, min. 10 15
Rate 1, °C/min. 1.1 1.3
tration of each component in mass % is determined by normal-
Final temperature 1, °C 114 70
ization of the peak areas after correction of selected compo-
Hold time 2, min. 0 0
nents with detector response factors. The unknown
Rate 2, °C/min 1.7 1.7
Final temperature 2, °C 250 250
components are reported individually as well as a summary
Final hold time 2, min. 5 20
total.
Injector, °C 250 250
Detector, °C 280 280
Carrier gas helium pressure, kPA (psi) 207 (30) 190 (27)
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Flow rate (initial isotherm), mL/min. 0.9 0.7
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Average linear velocity, cm/s 22 21.5
Standards volume information, refer to the standard’s Document Summary page on
Injection
the ASTM website.
Sample size, µL 0.5 0.3
The last approved version of this historical standard is referenced on Splitter vent–flow out, mL/min. 250 200
www.astm.org.
D6733 − 01 (2020)
TABLE 2 Reference Retention Times of Normal Paraffins
7.3 Oxidizing Gas, air, 99 mol %. (Warning—Compressed
gas under high pressure.)
NOTE 1—Minutes and tenths of a minute.
Method Method Method Method Method Method
7.4 n-Pentane, 99+ mol % pure. (Warning—Extremely
1 1 1 2 2 2
flammable. Harmful if inhaled.)
n-Paraffins Lower Refer- Upper Lower Refer- Upper
Time ence Time Time ence Time
7.5 n-Hexane, 99+ % mol % pure. (Warning—Extremely
Time Time
flammable. Harmful if inhaled.)
n-Heptane 18.5 19.4 20.3 39.5 40.7 42.0
n-Octane 32.0 33.0 34.0 57.0 57.8 59.0
7.6 n-Heptane, 99+ mol % pure. (Warning—Extremely
n-Dodecane 92.8 94.0 95.2 106.4 107.6 108.8
flammable. Harmful if inhaled.)
7.7 2-Methylheptane, 99+ mol % pure. (Warning—
Extremely flammable. Harmful if inhaled.)
7.8 4-Methylheptane, 99+ mol % pure. (Warning—
Initial temperature 35 °C
Extremely flammable. Harmful if inhaled.)
Hold time 50 min
Final temperature 220 °C
7.9 n-Octane, 99+ mol % pure. (Warning—Extremely
Hold time 20 min
Rate 3 °C ⁄min.
flammable. Harmful if inhaled.)
10.2 Column Evaluation—To perform the required
7.10 n-Dodecane, 99+ mol % pure. (Warning—Extremely
separation, the column must meet three criteria of separation:
flammable. Harmful if inhaled.)
efficiency, resolution, and polarity.
7.11 Toluene, 99+ mol % pure. (Warning—Extremely 10.2.1 Effıciency—The number of theoretical plates is cal-
flammable. Harmful if inhaled.)
culated with the normal octane peak using Eq 1:
n 5 5.545 Rt/W (1)
~ !
7.12 System Performance Mixture—Weigh an equal amount 0.5
of n-pentane, n-heptane, n-octane, n-dodecane,
where:
2-methylheptane, 4-methylheptane, and toluene. Dilute this
n = number of theoretical plates,
mixture in n-hexane to obtain a concentration of 2 % by mass
Rt = retention time of normal octane, and
for each compound.
W = mid-height peak width of normal octane in the same
0.5
unit as retention time.
8. Sampling
10.2.1.1 The number of theoretical plates must be greater
8.1 Container Sampling—Samples shall be taken as de-
than 200 000.
scribed in Practice D4057 for instructions on manual sampling
10.2.2 Resolution—Resolution is determined between the
into open container.
peaks of 2-methylheptane and 4-methylheptane using Eq 2:
8.2 The sample and a 2 mLvial must be cooled at 4 °C. Part
2 Rt 2 Rt
~ !
a b
~ ! ~ !
R 5 (2)
ofthesampleistransferredto the vial up to 80 %ofitsvolume,
1.699 W 1W
~ !
0.5~a! 0.5~b!
and aluminum cap with septum is crimped.
where:
Rt = retention time of 4-methylheptane,
9. Preparation of Apparatus
(a)
Rt = retention time of 2-methylheptane,
(b)
9.1 Installation—Install and condition column in accor-
W = mid-height peak width of 4-methylheptane in the
0.5(a)
dance with the supplier’s instruction.
same unit as retention time, and
W = mid-height peak width of 2-methylheptane in the
0.5(b)
9.2 Operating Conditions—Two sets of operating condi-
same unit as retention time.
tions are proposed in Table 1, the first with an initial column
temperature above the ambient temperature, the second with a
10.2.2.1 The resolution must be equal to 4 or greater than
sub-ambient column temperature profile. Adjust the operating
1.20.
conditions of the gas chromatograph to conform to the first or
10.2.3 Polarity—Polarity is defined by the McReynolds
second method.
constant of toluene, using Eq 3:
9.3 Carrier Gas Pressure—Set a correct carrier gas pressure Rn 5 Ki 2 Ki (3)
tol ana squalane
using the system performance mixture such that the retention
where:
time of n-Heptane, n-Octane and n-Dodecane are between the
Ki = toluene Kovats index on Squalane at
squalane
values given in Table 2.
35 °C = 742.6, and
Ki = tolueneKovatsindexontheanalyticalcolumnat
ana
10. System Performance Evaluation
35 °C.
10.1 Evaluation of the column and linearity of the split
10.2.3.1 Toluene Kovats index is calculated using Eq 4:
injection are carried out with a system performance mixture
logT' 2 logT'
R t R h
~ ! ~ !
defined in 7.12 and with the column temperature conditions
Ki 5 7001100 (4)
S D
ana
logT' 2 logT'
defined in the following table. R~o! R~h!
D6733 − 01 (2020)
where: 12.3 Integration of Chromatogram—Integration codes must
be selected to obtain a horizontal baseline with a perpendicular
T' = adjusted retention time for toluene,
R(t)
droptothebaselineforpartiallyresolvedpeaks.Anexampleof
T' = adjusted retention time for n-heptane, and
R(h)
T' = adjusted retention time for n-octane. correct baseline is given in Figs. A1.1 and A1.2.
R(o)
10.2.3.2 Adjusted retention time of a peak is determined by 12.4 Identification—Each peak is identified by matching the
subtracting the retention time of an unretained compound (air retentiontimewiththatofcompoundslistedinTable1orTable
2 and standard chromatogram given in Fig. A1.1 or Fig. A1.2.
or methane) from the retention time of the peak. The McReyn-
olds constant must be less than 10. Aspecific software program using the data of Table 1 or Table
2 can be employed.
10.2.4 Base Line Stability—Base line stability is calculated
with the difference between area slices at the beginning and at 12.4.1 If an oxygenate has been determined by Test Meth-
the end of analysis, divided by the maximum area slice of ods D4815 or D5599 and is not in the table, it is necessary to
N-octane obtained with the system performance mixture. prepare a mixture of a weighed amount of this oxygenate in a
10.2.4.1 Measurement of the Stability—Carry out one tem- known spark-ignition engine fuel to determine its retention
perature programming defined in 10.1 without injecting any time and response factor and then add it to the table.
sample. Subtract the area slices at the start of the analysis with
those corresponding to 120 min (average of three slices).
13. Calculation
10.2.4.2 Stability Standardization—Standardization is car-
13.1 Calculation of % (m/m) of Each Compound Without
ried out using the system performance mixture defined in 7.12
Co-elution and Not Corrected for Co-elutions—% (m/m) of
with the column temperature conditions defined in 10.1. The
each component without co-elution and no corrections of
value obtained in 10.2.4.1 is divided by the maximum area
co-elutions is calculated according to Eq 6:
slice of N-octane and multiplied by 100. The value obtained
A B
i i
must be less than 2 %. If this is not the case, check for possible
C 5 100 (6)
i5n
i'
leaks, or recondition the column according to the manufactur-
~A B 1A B !
( i i int int
i50
er’s recommendations.
10.3 Evaluation of the Linearity of the Split Injector— where:
Evaluationiscarriedoutusingthesystemperformancemixture
C = % (m/m) of compound i without co-elution and no
i'
definedin7.12withthecolumntemperatureconditionsdefined
correction of coelutions,
in 10.1. The % (m/m) of each compound is determined from
Ai = peak area of compound i without co-elution (benzene,
the corrected area % using the response factors for each
toluene, and oxygenates),
compound given in Table A1.1 or Table A1.2. The relative A = peak area of compounds co-eluting (benzene, toluene,
int
percent error is determined from the known mixture concen- and oxygenates),
B = response factor for component i (given in Table A1.1
trations according to Eq 5:
i
or Table A1.2), and
Relative% error
B = response factor for components co-eluted with
int
100 ~calculated concentration 2 known concentration!
benzene, toluene, and oxygenates.
known concentration
13.2 Calculation of Components Coeluted with Benzene,
(5)
Toluene, and Oxygenates—Benzene and toluene contents are
10.3.1 The relative error must not exceed 3 %.
determined by Test Methods D3606 or D4420 or D5580;
oxygenates content is determined by Test Methods D4815 or
11. Response Factor
D5599. The % (m/m) of components coeluted with benzene,
toluene, and oxygenates is calculated according Eq 7:
11.1 Theoretical response factors are used for correction of
the detector response of hydrocarbons. The response factor for
B B
int int
C 5 C 0.01 100 2 C 2 C 3 2 C 3 (7)
F S DG
coeluted int ( ext ext ext
each compound is relative to that of benzene taken equal to
B B
ext ext
unity and is listed in Tables 1 and 2. For peaks corresponding
where:
to the co-elution of compounds with benzene, toluene, and
C = % (m/m) of component eluted with benzene,
oxygenates, the response factor is the one of the co-eluted
coeluted
toluene, or oxygenates,
compound of % (m/m). Co-eluted compounds are footnoted in
C = % (m/m) calculated with Eq 6 for the peak with
Tables A1.1 and A1.2. int
co-elution,
C = % (m/m) of benzene, toluene, or oxygenates
ext
12. Procedure
determined by other method, and
12.1 Preparation of Apparatus—After optimization of the
B = response factor of benzene, toluene, or
ext
carrier gas pressure (9.3) and evaluation of apparatus (Section
oxygenates.
10), set the temperature program corresponding to the selected
13.3 Calculation of Other Components—% (m/m) of other
method (Table 1).
components is calculated using Eq 8:
12.2 Injection of Sample—Inject with a 5 µL or 10 µL
100 2 C 2 C
syringe, manually or by autosampler, the size corresponding to ( coeluted ( ext.
C 5 C (8)
i i'
the method (Table 1). C
( i'
D6733 − 01 (2020)
14. Report material, in the normal and correct operation of the test
method, would exceed the value given in the Table 3 in only
14.1 Report the content of each component as % (m/m) to
one case in twenty.
the nearest 0.01 %.
15.1.2 Reproducibility—The difference between two single
and independent results, obtained by different operators in
15. Precision
different laboratories on nominally identical test material, in
15.1 Individual Components—The precision of this test
the normal and correct operation of the test method, would
method was determined by a statistical analysis of interlabo-
exceed the values given in the Table 3 in only one case in
ratorytestresults.Itappliesonlytoarangefrom0.1 %to15 %
twenty.
(m/m), for all components with a resolution greater than 1.0
and without co-elution with oxygenate components. When two
16. Keywords
components of the same hydrocarbon type have a resolution
16.1 detailed hydrocarbon analysis; DHA; gas chromatog-
less than 1.0, the precision can be applied by adding the
raphy;gasoline;hydrocarbons;opentubular;oxygenates;spark
concentrationoftwocomponents.Theprecisionisthesamefor
ignition engine fuels
all: (a) light components (saturates and olefins) with a carbon
number of 4 and 5, (b) saturates and olefins with a range of
TABLE 3 Repeatability and Reproducibility for Individual
carbon number from 6 to 12, and to (c) aromatics. This
Components
precision is as follows:
Range
15.1.1 Repeatability—The difference between successive
Range, Repeatability, Reproducibility,
of
% (m/m) X (%(m/m)) X(%(m/m))
test results, obtained by the same operator with the same
Carbon
apparatus under constant operating conditions on identical test
Light C4–C5 0.1–14 0.04 · X 0.16 · X
Components
Paraffins C6–C12 0.1–11.5 0.01 + 0.03 · X 0.04 + 0.07 · X
Supporting data of interlaboratory cooperative study program, statistical
Naphthenes C6–C8 0.1–3
analysis, and precision determination are available from ASTM International Olefins C6–C8 0.1–1
Headquarters. Request RR: D02:1520. Contact ASTM Customer Service at Aromatics C6–C12 0.1–14 0.05 + 0.02 · X 0.1 + 0.06 · X
[e-mail].
ANNEX
(Mandatory Information)
A1. METHOD 1, PEAK NUMBER, RETENTION TIME, RESPONSE FACTOR, HYDROCARBON TYPE, AND CARBON NUM-
BER
A1.1 Table A1.1 and Table A1.2 include Method 1/Method Fig. A1.2 include Method 1/Method 2 reference
2 peak numbers, retention time, response factor, hydrocarbon
chromatograms.
type, and carbon number for each component. Fig. A1.1 and
D6733 − 01 (2020)
TABLE A1.1 Method 1–Peak Numbers, Retention Time, Response Factor, Hydrocarbon Type and Carbon Number for Each Component
NOTE 1—Legend—Hydrocarbon types–NP = normal paraffins, IP = isoparaffins, NA = naphthenes, OL = olefins, AR = aromatics, Ox = oxygenates.
Nb Compounds Retention, min. Response Factor Hydrocarbon Type Carbon No.
1 Propane 4.14 1.125 Ip 3
A
2 Isobutane 4.47 1.112 Ip 4
A
2 Methanol 4.47 2.850 Ox 1
3 Isobutene+1-butene 4.66 1.075 Ol 4
4 N-butane 4.74 1.112 NP 4
5 Trans-2-butene 4.84 1.075 Ol 4
6C -diolefin 4.88 1.045 OL 4
7 CIS-2-butene 5.00 1.075 OL 4
8 Ethanol 5.17 2.300 OX 2
9 3-Methyl-1-butene 5.45 1.075 OL 5
10 Isopentane 5.76 1.105 IP 5
11 1-pentene 6.05 1.075 OL 5
12 2-Methyl-1-butene 6.20 1.075 OL 5
13 N-Pentane 6.31 1.105 NP 5
14 Isoprene 6.43 1.075 OL 5
15 Trans-2-pentene 6.49 1.075 OL 5
16 Tertiobutylalcohol 6.60 1.490 OX 5
17 CIS-2-pentene 6.70 1.075 OL 5
18 2-Methyl-2-butene 6.84 1.075 OL 5
19 1,Trans-3-pentadiene 6.91 1.075 OL 5
20 1,CIS-3-pentadiene 7.28 1.075 OL 5
21 2,2-Dimethylbutane 7.36 1.100 IP 6
22 1-Cyclopentene 7.99 1.075 OL 5
23 4-Methyl-1-pentene 8.12 1.075 OL 6
24 3-Methyl-1-pentene 8.19 1.075 OL 6
A
25 Cyclopentane 8.46 1.075 NA 5
A
25 MTBE 8.46 1.520 OX 5
26 2,3-Dimethylbutane 8.52 1.100 IP 6
27 4-Methyl-CIS-2-pentene 8.61 1.075 OL 6
28 2-Methylpentane 8.70 1.100 IP 6
29 4-Methyl-trans-2-pentene 9.04 1.075 OL 6
30 3-Methylpentane 9.41 1.100 IP 6
31 2-Methyl-1-pentene 9.66 1.075 OL 6
32 1-Hexene 9.70 1.075 OL 6
33 2-Ethyl-1-butene 10.32 1.075 OL 6
34 N-Hexane 10.40 1.110 NP 6
35 Trans-3-hexene 10.51 1.075 OL 6
36 CIS-3-hexene 10.59 1.075 OL 6
37 Trans-2-hexene 10.69 1.075 OL 6
38 2-Methyl-2-pentene 10.84 1.075 OL 6
39 4-Methyl-1-cyclopentene 10.99 1.075 OL 6
40 3-Methyl-trans-2-pentene 11.06 1.075 OL 6
41 3-Methyl-1-cyclopentene 11.19 1.075 OL 6
42 CIS-2-Hexene 11.31 1.075 OL 6
43 C -olefin 11.46 1.075 OL 6
44 ETBE 11.62 1.520 OX 6
45 3-Methyl-CIS-2-pentene 11.74 1.075 OL 6
46 2,2-Dimethylpentane 12.06 1.099 IP 7
47 1-Methylcyclopentane 12.23 1.075 NA 6
48 2,4-Dimethylpentane 12.53 1.099 IP 7
49 C -olefin 12.78 1.075 OL 6
50 2,2,3-Trimethylbutane 13.93 1.099 IP 7
51 C -olefin 13.08 1.075 OL 6
52 C -olefin 13.45 1.075 OL 7
53 C -olefin 13.56 1.075 OL 7
54 C -olefin 13.84 1.075 OL 7
55 C -olefin 13.93 1.075 OL 7
A
56 Benzene 14.08 1.000 AR 6
A
56 1-Methyl-1-cyclopentene 14.08 1.075 OL 6
57 C -olefin 14.23 1.075 OL 7
58 C -olefin 14.36 1.075 OL 7
59 3,3-Dimethylpentane 14.61 1.099 IP 7
60 C -olefin 14.77 1.075 OL 7
61 Cyclohexane 14.93 1.075 NA 6
62 C -olefin 15.13 1.075 OL 7
63 C -olefin 15.24 1.075 OL 7
64 C -olefin 15.44 1.075 OL 7
65 C -olefin 15.68 1.075 OL 7
66 2-Methylhexane 15.84 1.099 IP 7
67 2,3-Dimethylpentane 15.99 1.099 IP 7
68 1,1-Dimethylcyclopentane 16.24 1.075 NA 7
69 Cyclohexene 16.44 1.075 OL 6
70 3-Methylhexane 16.70 1.099 IP 7
D6733 − 01 (2020)
TABLE A1.1 Continued
Nb Compounds Retention, min. Response Factor Hydrocarbon Type Carbon No.
71 C -olefin 17.04 1.075 OP 7
72 CIS-1,3- 17.32 1.075 NA 7
dimethylcyclopentane
73 Trans-1,3- 17.61 1.075 NA 7
dimethylcyclopentane
74 3-ethylpentane 17.76 1.099 IP 7
75 Trans-1,2- 17.92 1.075 NA 7
dimethylcyclopentane
76 2,2,4-Trimethylpentane 18.16 1.096 IP 8
76 C -olefin 18.16 1.075 OL 7
77 C -olefin 18.74 1.075 OL 7
78 C -olefin 19.13 1.075 OL 7
79 N-heptane 19.36 1.099 NP 7
80 C -olefin 19.57 1.075 OL 7
81 C -olefin 19.69 1.075 OL 7
82 C -olefin 19.90 1.075 OL 7
83 C -olefin 20.08 1.075 OL 7
84 C -olefin 20.47 1.075 OL 7
85 C -olefin 2
...