ASTM D8003-15a(2021)

Standard Test Method for Determination of Light Hydrocarbons and Cut Point Intervals in Live Crude Oils and Condensates by Gas Chromatography

SIGNIFICANCE AND USE
5.1 This test method determines methane (nC1) to hexane (nC6), cut point carbon fraction intervals to nC24 and recovery (nC24+) of live crude oils and condensates without depressurizing, thereby avoiding the loss of highly volatile components and maintaining sample integrity. This test method provides a highly resolved light end profile which can aid in determining and improving appropriate safety measures and product custody transport procedures. Decisions in regards to marketing, scheduling, and processing of crude oils may rely on light end compositional results.  
5.2 Equation of state calculations can be applied to variables provided by this method to allow for additional sample characterization.
SCOPE
1.1 This test method covers the determination of light hydrocarbons and cut point intervals by gas chromatography in live crude oils and condensates with VPCR4 (see Note 1) up to 500 kPa at 37.8 °C.
Note 1: As described in Test Method D6377.  
1.2 Methane (C1) to hexane (nC6) and benzene are speciated and quantitated. Samples containing mass fractions of up to 0.5 % methane, 2.0 % ethane, 10 % propane, or 15 % isobutane may be analyzed. A mass fraction with a lower limit of 0.001 % exists for these compounds.  
1.3 This test method may be used for the determination of cut point carbon fraction intervals (see 3.1.1) of live crude oils and condensates from initial boiling point (IBP) to 391 °C (nC24). The nC24 plus fraction is reported.  
1.4 Dead oils or condensates sampled in accordance with 12.1 may also be analyzed.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5.1 Exception—Where there is no direct SI equivalent such as tubing size.  
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.  
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.

General Information

• Status: Historical
• Publication Date: 31-Dec-2020
• ICS: 75.040 - Crude petroleum
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.04.0L - Gas Chromatography Methods

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: D8003 − 15a (Reapproved 2021)
Standard Test Method for
Determination of Light Hydrocarbons and Cut Point
Intervals in Live Crude Oils and Condensates by Gas
Chromatography
This standard is issued under the fixed designation D8003; 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 2. Referenced Documents
1.1 This test method covers the determination of light 2.1 ASTM Standards:
hydrocarbonsandcutpointintervalsbygaschromatographyin D1265 Practice for Sampling Liquefied Petroleum (LP)
live crude oils and condensates withVPCR (see Note 1)upto Gases, Manual Method
500 kPa at 37.8 °C. D3700 Practice for Obtaining LPG Samples Using a Float-
ing Piston Cylinder
NOTE 1—As described in Test Method D6377.
D4307 Practice for Preparation of Liquid Blends for Use as
1.2 Methane(C )tohexane(nC )andbenzenearespeciated
1 6
Analytical Standards
and quantitated. Samples containing mass fractions of up to
D5002 Test Method for Density, Relative Density, and API
0.5 % methane, 2.0 % ethane, 10 % propane, or 15 % isobu-
Gravity of Crude Oils by Digital Density Analyzer
tane may be analyzed. A mass fraction with a lower limit of
D6299 Practice for Applying Statistical Quality Assurance
0.001 % exists for these compounds.
and Control Charting Techniques to Evaluate Analytical
1.3 This test method may be used for the determination of Measurement System Performance
D6377 Test Method for Determination of Vapor Pressure of
cut point carbon fraction intervals (see 3.1.1) of live crude oils
and condensates from initial boiling point (IBP) to 391 °C Crude Oil: VPCR (Expansion Method)
x
D6792 Practice for Quality Management Systems in Petro-
(nC ). The nC plus fraction is reported.
24 24
leum Products, Liquid Fuels, and Lubricants Testing
1.4 Dead oils or condensates sampled in accordance with
Laboratories
12.1 may also be analyzed.
E1510 Practice for Installing Fused Silica Open Tubular
1.5 The values stated in SI units are to be regarded as
Capillary Columns in Gas Chromatographs
standard. No other units of measurement are included in this
2.2 Other Regulations:
standard.
CAN/CGSB-3.0 No. 14.3-99 Standard Test Method for the
1.5.1 Exception—Where there is no direct SI equivalent
Identification of Hydrocarbon Components inAutomotive
such as tubing size.
Gasoline using Gas Chromatography
1.6 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the 3. Terminology
responsibility of the user of this standard to establish appro-
3.1 Definitions:
priate safety, health, and environmental practices and deter-
3.1.1 cut point carbon fraction interval, n—thepercentmass
mine the applicability of regulatory limitations prior to use.
obtained between two selected n-paraffins of the interval. The
1.7 This international standard was developed in accor-
cut point carbon fraction interval as used in this test method is
dance with internationally recognized principles on standard-
defined as the percent mass obtained between the end of one
ization established in the Decision on Principles for the
n-paraffin peak to the end of the next n-paraffin peak, thus a
Development of International Standards, Guides and Recom-
temperature interval is not used to determine the cut points but
mendations issued by the World Trade Organization Technical
rather the end points sequential of a n-paraffin peak pair.
Barriers to Trade (TBT) Committee.
1 2
This test method is under the jurisdiction of ASTM Committee D02 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Subcommittee D02.04.0L on Gas Chromatography Methods. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Jan. 1, 2021. Published February 2021. Originally the ASTM website.
approved in 2015. Last previous edition approved in 2015 as D8003 – 15a. DOI: Available from Standards Council of Canada (SCC), 600–55 Metcalfe St.,
10.1520/D8003-15AR21. Ottowa, ON K1P 6L5, http://www.scc.ca.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D8003 − 15a (2021)
3.1.2 D1265 cylinder, n—a container used for storage and provides a highly resolved light end profile which can aid in
transportation of a sample obtained at pressures above atmo- determining and improving appropriate safety measures and
spheric pressure as described in Practice D1265. product custody transport procedures. Decisions in regards to
marketing, scheduling, and processing of crude oils may rely
3.1.3 dead crude oil, n—a term usually employed for crude
on light end compositional results.
oils that, when exposed to normal atmospheric pressure at
room temperature, will not result in actual boiling of the
5.2 Equationofstatecalculationscanbeappliedtovariables
sample.
provided by this method to allow for additional sample
3.1.3.1 Discussion—These crudes will have vapor pressures
characterization.
below atmospheric pressure at room temperature.
6. Apparatus
3.1.4 floating piston cylinder, n—a high pressure sample
6.1 Gas Chromatograph—The recommended conditions of
container, with a free floating internal piston that effectively
the gas chromatograph are listed in Table 1.The gas chromato-
divides the container into two separate compartments, as
graph shall be equipped with an electronic pressure control
described in Practice D3700.
(EPC) or manual split/splitless inlet system. A 4-way 24 VDC
3.1.5 live crude oil, n—crudeoilwithsufficientlyhighvapor
solenoid valve controlled from the gas chromatograph key-
pressure that it would boil if exposed to normal atmospheric
board for actuator air pressure control to accommodate the
pressure at room temperature.
HPLIS is also required. Important features of instrument
3.1.5.1 Discussion—Sampling and handling of live crude
components are listed in section 6.2 to 6.4.
oils requires a pressurized sample system and pressurized
6.2 Data System—A data system capable of measuring the
sample containers to ensure sample integrity and prevent loss
of volatile components. retention time and areas of eluting peaks accurately and
repeatedly as well as possess a data rate to achieve 10 points to
3.1.6 residue, n—the percent mass of the sample that either
20 points per peak.
does not elute from the column or elutes after the end of the
nC peak. 6.3 Flame Ionization Detector (FID)—A FID system shall
be connected to the column to avoid any cold spots and have
3.1.7 vapor pressure of crude oil (VPCR ), n—the pressure
x
the ability to operate at a temperature equivalent to the
exerted in an evacuated chamber at a vapor-liquid ratio of X:1
maximum column temperature used. The detector shall have
by conditioned or unconditioned crude oil, which may contain
sufficient sensitivity to detect n-heptane at a mass fraction of
gas, air, or water, or a combination thereof, where X may vary
0.01 % with a signal-to-noise greater than 5.
from 4 to 0.02.
6.4 Heated Pressure Liquid Injection System (HPLIS)—A
4. Summary of Test Method
HPLIS system that is compatible with a split/splitless inlet and
4.1 This is a gas chromatographic method using a Heated capable of linearly introducing C to C components should
1 24
Pressurized Liquid Injection System (HPLIS) (trademarked) ,
be used. The unit should possess an internal dead volume of
split/splitless inlet, capillary column, and flame ionization ≤80 µL in sample transfer zone and a 0.5 uL stem volume to
detector. A calibration mixture which fully elutes from the
contain the pressurized liquid sample. The sample pressure
capillary column, consisting of a full range of hydrocarbons
including methane, ethane, and normal paraffins up to C is
TABLE 1 Gas Chromatograph Parameters
used to ensure system performance (Section 7). This calibra-
Initial Oven Temperature 35 °C
tion mixture serves as an external response standard to deter- Initial Oven Time 2 min
Oven Temperature Program 20 °C/min
mine sample recovery. Samples are introduced to the GC
Final Oven Temperature 310 °C
systembyloadingtheHPLISvalveunderpressurefollowedby
Final Hold Time 10 min
the pneumatic piston action of the HPLIS injection system
HPLIS Collar Heater Temperature 200 °C
introducing the sample into the gas chromatographic injection
port.
Inlet Temperature 400 °C
Column 15m×0.28mm×3µm PDMS
5. Significance and Use
Column Flow (Hydrogen) 2 mL/min
5.1 This test method determines methane (nC ) to hexane
Carrier Control Constant Flow
(nC ), cut point carbon fraction intervals to nC and recovery
6 24
Detector FID
(nC +) of live crude oils and condensates without
Detector Temperature 425 °C
depressurizing, thereby avoiding the loss of highly volatile
Detector Gases:
Hydrogen 40 mL/min
componentsandmaintainingsampleintegrity.Thistestmethod
Air 450 mL/min
Make-Up (N ) 25 mL/min
HPLIS (trademarked) has been found to be a suitable injector. The sole source
Volume Injected 0.5 µL
of supply of the HPLIS known to the committee at this time is Transcendent
Split Ratio 30:1
Enterprises Inc., #33: 17715 - 96 Ave Edmonton, Alberta, Canada, T5T 6W9,
Data Acquisition Rate 10 Hz
www.transcendent.ca. If you are aware of alternative suppliers, please provide this
HPLIS Valve Timing On 0 min
information to ASTM International Headquarters. Your comments will receive
HPLIS Valve Timing Off 0.3 min
careful consideration at a meeting of the responsible technical committee, which Total Acquisition Time 25.75 min
you may attend.
D8003 − 15a (2021)
rating for the unit should be ≥8300 kPa (1200 psig) at 30 °C 7.4 The sensitivity of the system shall be determined by
using helium as the test media. Other injection systems may be analyzing a 10 mg⁄kg pentane standard (Practice D4307). The
employed provided the performance criteria in Section 7 are signal to noise ratio shall be greater than 5.
met.
8. Reagents and Materials
7. Column and Performance Criteria
8.1 Gas Chromatograph Gases—The purity of the volume
fraction for all gases used in this system should be≥99.995 %.
7.1 A 100 % polydimethylsiloxane (PDMS) phase column
8.1.1 Carrier Gas—Hydrogen. Follow proper safety proce-
of a 15 m length with an inside diameter of 0.28 mm and 3 µm
dures. (Warning—Extremely flammable under high pressure;
film thickness is recommended. The column shall possess
use of a safety hydrogen sensor in GC oven containing the
stability at 380 °C. Metal columns have been successfully used
column is highly recommended.)
for this test method. The column should be installed according
8.1.2 Detector Gases—Air, hydrogen, and make-up gas
to Practice E1510. To prevent column overloading, the skew-
(helium or nitrogen) are used for Flame Ionization Detector
ness is measured for nC . The value shall not be less than 1 or
operation (Warning—Compressed gas under high pressure.
more than 4. Skewness is determined drawing a straight line
Hydrogen is extremely flammable under high pressure.)
downtheapex,aswellasoneacrossthelengthofthenC peak
8.1.3 Injection System Wash—Methylene chloride, with a
at 5 % height.The width of the right section of the peak at 5 %
purity of 99 %, used to remove any residual components from
height (B) is divided by that of the left section (A) (see Fig. 1).
HPLIS sample injection. (Warning—Toxic material. May be
7.2 Baseline resolution for C ,C ,C , isobutane and butane
1 2 3
combustible at high temperatures.) Toluene, with a purity of
shall be achieved (R ≥ 1.0). The resolution is calculated as
99 %, or other suitable solvents may be used as an alternative
follows:
to methylene chloride but caution shall be taken to eliminate
R 5 2 3 ~t 2 2 t 1!⁄1.699~w 1 1 w 2! (1) residual sample and solvent in the HPLIS sample lines.
8.1.4 Calibration Standard—The calibration standard may
where:
serve three purposes. A retention time calibration for
t2 = retention time of peak 1,
n-paraffins covering the range of C to nC , the determination
1 24
t1 = retention time of peak 2,
of the detector response to enable the sample recovery calcu-
w1 = peak width at half height for peak 1, and
lation and a linearity check sample. A hydrocarbon mixture
w2 = peak width at half height for peak 2.
such as a gasoline mid-distillate (diesel or jet fuel) containing
7.3 Splitter Linearity Verification—Using the calibration
a known amount of C,C,C,nC , and n-paraffins in the
1 2 3 5
standard (see 8.1.4), inject this sample according to the
range of nC through nC is required.All n-paraffins present
17 24
parameters listed in Table 1. Identify and quantify the normal
up to nC shall be identifiable. The calibration standard shall
paraffins C to C . Compare the calculated mass % concen-
1 24 completely elute from the column by peak end of nC under
trations to the known standard concentrations after calculating
the conditions of the method. A commercially prepared cali-
the corrected area normalization using the response factors
bration standard or one prepared as described in theAppendix
from Table 2 procedures in Section 13. Verify that for each
of this method has been found to be successful.
component selected, its concentration does not vary by more
than 3 % relative error.
9. Preparation of Apparatus
percent relative error5
9.1 Install the HPLIS system according to supplier proce-
concentration determined 2 concentration known dures. The unit should have one of the sample chamber tubes
~ ! (2)
100 3
concentration known connected to an isolation (needle) valve to allow control and
FIG. 1 Calculation of Peak Skewness
D8003 − 15a (2021)
A
TABLE 2 Component Properties and Theoretical Response Factors
Generalized Molecular Generalized Density of
Generalized Boiling
Molecular Weight of Density of Compound Weight of Cut Point Cut Point Fraction Theoretical Mass
Component Point of Cut Point
Compound (g/mol) @20°C(g/mL) Fraction Interval Interval @ 20 °C Response Factor
Fraction Interval °C
(g/mol) (g/mL)
C 16.04 0.26 1.00
C 30.08 0.34 0.937
C 44.10 0.505 0.916
iC 58.12 0.557 0.906
n-C 58.12 0.5788 0.906
iC 72.15 0.6201 0.899
n-C 72.15 0.6262 0.899
n-C 86.18 0.6603 63.9 84 0.685 0.895
Benzene 78.12 0.8765 0.812
n-C 100.21 0.6837 91.9 96 0.722 0.892
n-C 114.22 0.7025 116.7 107 0.745 0.890
n-C 128.26 0.7176 142.2 121 0.764 0.888
n-
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
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: D8003 − 15a D8003 − 15a (Reapproved 2021)
Standard Test Method for
Determination of Light Hydrocarbons and Cut Point
Intervals in Live Crude Oils and Condensates by Gas
Chromatography
This standard is issued under the fixed designation D8003; 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*Scope
1.1 This test method covers the determination of light hydrocarbons and cut point intervals by gas chromatography in live crude
oils and condensates with VPCR (see Note 1) up to 500 kPa at 37.8 °C.
NOTE 1—As described in Test Method D6377.
1.2 Methane (C ) to hexane (nC ) and benzene are speciated and quantitated. Samples containing mass fractions of up to 0.5 %
1 6
methane, 2.0 % ethane, 10 % propane, or 15 % 0.5 % methane, 2.0 % ethane, 10 % propane, or 15 % isobutane may be analyzed.
A mass fraction with a lower limit of 0.001 % 0.001 % exists for these compounds.
1.3 This test method may be used for the determination of cut point carbon fraction intervals (see 3.1.23.1.1) of live crude oils
and condensates from initial boiling point (IBP) to 391 °C (nC ). The nC plus fraction is reported.
24 24
1.4 Dead oils or condensates sampled in accordance with 12.1 may also be analyzed.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5.1 Exception—Where there is no direct SI equivalent such as tubing size.
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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
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:
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 Dec. 1, 2015Jan. 1, 2021. Published February 2016February 2021. Originally approved in 2015. Last previous edition approved in 2015 as
D8003 – 15.D8003 – 15a. DOI: 10.1520/D8003-15A.10.1520/D8003-15AR21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*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
D8003 − 15a (2021)
D1265 Practice for Sampling Liquefied Petroleum (LP) Gases, Manual Method
D3700 Practice for Obtaining LPG Samples Using a Floating Piston Cylinder
D4307 Practice for Preparation of Liquid Blends for Use as Analytical Standards
D5002 Test Method for Density, Relative Density, and API Gravity of Crude Oils by Digital Density Analyzer
D6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measure-
ment System Performance
D6377 Test Method for Determination of Vapor Pressure of Crude Oil: VPCR (Expansion Method)
x
D6792 Practice for Quality Management Systems in Petroleum Products, Liquid Fuels, and Lubricants Testing Laboratories
E1510 Practice for Installing Fused Silica Open Tubular Capillary Columns in Gas Chromatographs
2.2 Other Regulations:
CAN/CGSB-3.0 No. 14.3-99 Standard Test Method for the Identification of Hydrocarbon Components in Automotive Gasoline
using Gas Chromatography
3. Terminology
3.1 Definitions:
3.1.1 D1265 cylinder, n—a container used for storage and transportation of a sample obtained at pressures above atmospheric
pressure as described in Practice D1265.
3.1.1 cut point carbon fraction interval, n—the percent mass obtained between two selected n-paraffins of the interval. The cut
point carbon fraction interval as used in this test method is defined as the percent mass obtained between the end of one n-paraffin
peak to the end of the next n-paraffin peak, thus a temperature interval is not used to determine the cut points but rather the end
points sequential of a n-paraffin peak pair.
3.1.2 D1265 cylinder, n—a container used for storage and transportation of a sample obtained at pressures above atmospheric
pressure as described in Practice D1265.
3.1.3 dead crude oil, n—a term usually employed for crude oils that, when exposed to normal atmospheric pressure at room
temperature, will not result in actual boiling of the sample.
3.1.3.1 Discussion—
These crudes will have vapor pressures below atmospheric pressure at room temperature.
3.1.4 floating piston cylinder, n—a high pressure sample container, with a free floating internal piston that effectively divides the
container into two separate compartments, as described in Practice D3700.
3.1.5 live crude oil, n—crude oil with sufficiently high vapor pressure that it would boil if exposed to normal atmospheric pressure
at room temperature.
3.1.5.1 Discussion—
Sampling and handling of live crude oils requires a pressurized sample system and pressurized sample containers to ensure sample
integrity and prevent loss of volatile components.
3.1.6 residue, n—the percent mass of the sample that either does not elute from the column or elutes after the end of the nC peak.
3.1.7 vapor pressure of crude oil (VPCR ), n—the pressure exerted in an evacuated chamber at a vapor-liquid ratio of X:1 by
x
conditioned or unconditioned crude oil, which may contain gas, air, or water, or a combination thereof, where X may vary from
4 to 0.02.
4. Summary of Test Method
4.1 This is a gas chromatographic method using a Heated Pressurized Liquid Injection System (HPLIS) (trademarked) ,
split/splitless inlet, capillary column, and flame ionization detector. A calibration mixture which fully elutes from the capillary
column, consisting of a full range of hydrocarbons including methane, ethane, and normal paraffins up to C is used to ensure
Available from Standards Council of Canada (SCC), 600–55 Metcalfe St., Ottowa, ON K1P 6L5, http://www.scc.ca.
HPLIS (trademarked) has been found to be a suitable injector. The sole source of supply of the HPLIS known to the committee at this time is Transcendent Enterprises
Inc., #33: 17715 - 96 Ave Edmonton, Alberta, Canada, T5T 6W9, www.transcendent.ca. 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.
D8003 − 15a (2021)
system performance (Section 7). This calibration mixture serves as an external response standard to determine sample recovery.
Samples are introduced to the GC system by loading the HPLIS valve under pressure followed by the pneumatic piston action of
the HPLIS injection system introducing the sample into the gas chromatographic injection port.
5. Significance and Use
5.1 This test method determines methane (nC ) to hexane (nC ), cut point carbon fraction intervals to nC and recovery (nC +)
1 6 24 24
of live crude oils and condensates without depressurizing, thereby avoiding the loss of highly volatile components and maintaining
sample integrity. This test method provides a highly resolved light end profile which can aid in determining and improving
appropriate safety measures and product custody transport procedures. Decisions in regards to marketing, scheduling, and
processing of crude oils may rely on light end compositional results.
5.2 Equation of state calculations can be applied to variables provided by this method to allow for additional sample
characterization.
6. Apparatus
6.1 Gas Chromatograph—The recommended conditions of the gas chromatograph are listed in Table 1. The gas chromatograph
shall be equipped with an electronic pressure control (EPC) or manual split/splitless inlet system. A 4-way 24 VDC solenoid valve
controlled from the gas chromatograph keyboard for actuator air pressure control to accommodate the HPLIS is also required.
Important features of instrument components are listed in section 6.2 to 6.4.
6.2 Data System—A data system capable of measuring the retention time and areas of eluting peaks accurately and repeatedly as
well as possess a data rate to achieve 10 points to 20 points per peak.
6.3 Flame Ionization Detector (FID)—A FID system shall be connected to the column to avoid any cold spots and have the ability
to operate at a temperature equivalent to the maximum column temperature used. The detector shall have sufficient sensitivity to
detect n-heptane at a mass fraction of 0.01 % with a signal-to-noise greater than 5.
6.4 Heated Pressure Liquid Injection System (HPLIS)—A HPLIS system that is compatible with a split/splitless inlet and capable
of linearly introducing C to C components should be used. The unit should possess an internal dead volume of ≤80 μL in sample
1 24
transfer zone and a 0.5 uL stem volume to contain the pressurized liquid sample. The sample pressure rating for the unit should
be ≥8300 kPa (1200 psig) at 30 °C using helium as the test media. Other injection systems may be employed provided the
performance criteria in Section 7 are met.
TABLE 1 Gas Chromatograph Parameters
Initial Oven Temperature 35 °C
Initial Oven Time 2 min
Oven Temperature Program 20 °C/min
Final Oven Temperature 310 °C
Final Hold Time 10 min
HPLIS Collar Heater Temperature 200 °C
Inlet Temperature 400 °C
Column 15 m × 0.28 mm × 3 μm PDMS
Column Flow (Hydrogen) 2 mL/min
Carrier Control Constant Flow
Detector FID
Detector Temperature 425 °C
Detector Gases:
Hydrogen 40 mL/min
Air 450 mL/min
Make-Up (N ) 25 mL/min
Volume Injected 0.5 μL
Split Ratio 30:1
Data Acquisition Rate 10 Hz
HPLIS Valve Timing On 0 min
HPLIS Valve Timing Off 0.3 min
Total Acquisition Time 25.75 min
D8003 − 15a (2021)
7. Column and Performance Criteria
7.1 A 100 % polydimethylsiloxane (PDMS) phase column of a 15 m length with an inside diameter of 0.28 mm and 3 μm film
thickness is recommended. The column shall possess stability at 380 °C. Metal columns have been successfully used for this test
method. The column should be installed according to Practice E1510. To prevent column overloading, the skewness is measured
for nC . The value shall not be less than 1 or more than 4. Skewness is determined drawing a straight line down the apex, as well
as one across the length of the nC peak at 5 % height. The width of the right section of the peak at 5 % height (B) is divided by
that of the left section (A) (see Fig. 1).
7.2 Baseline resolution for C , C , C , isobutane and butane shall be achieved (R ≥ 1.0). The resolution is calculated as follows:
1 2 3
R 5 23~t 2 2 t 1!⁄1.699~w 1 1 w 2! (1)
where:
t2 = retention time of peak 1,
t1 = retention time of peak 2,
w1 = peak width at half height for peak 1, and
w2 = peak width at half height for peak 2.
7.3 Splitter Linearity Verification—Using the calibration standard (see 8.1.4), inject this sample according to the parameters listed
in Table 1. Identify and quantify the normal paraffins C to C . Compare the calculated mass % concentrations to the known
1 24
standard concentrations after calculating the corrected area normalization using the response factors from Table 2 procedures in
Section 13. Verify that for each component selected, its concentration does not vary by more than 3 % relative error.
percent relative error5
concentration determined 2 concentration known
~ ! (2)
100 3
concentration known
7.4 The sensitivity of the system shall be determined by analyzing a 10 mg ⁄kg pentane standard (Practice D4307). The signal to
noise ratio shall be greater than 5.
8. Reagents and Materials
8.1 Gas Chromatograph Gases—The purity of the volume fraction for all gases used in this system should be ≥99.995 %.
8.1.1 Carrier Gas—Hydrogen. Follow proper safety procedures. (Warning—Extremely flammable under high pressure; use of a
safety hydrogen sensor in GC oven containing the column is highly recommended.)
8.1.2 Detector Gases—Air, hydrogen, and make-up gas (helium or nitrogen) are used for Flame Ionization Detector operation
(Warning—Compressed gas under high pressure. Hydrogen is extremely flammable under high pressure.)
FIG. 1 Calculation of Peak Skewness
D8003 − 15a (2021)
A
TABLE 2 Component Properties and Theoretical Response Factors
Generalized Molecular Generalized Density of
Generalized Boiling
Molecular Weight of Density of Compound Weight of Cut Point Cut Point Fraction Theoretical Mass
Component Point of Cut Point
Compound (g/mol) @ 20 °C (g/mL) Fraction Interval Interval @ 20 °C Response Factor
Fraction Interval °C
(g/mol) (g/mL)
C 16.04 0.26 1.00
C 30.08 0.34 0.937
C 44.10 0.505 0.916
iC 58.12 0.557 0.906
n-C 58.12 0.5788 0.906
iC 72.15 0.6201 0.899
n-C 72.15 0.6262 0.899
n-C 86.18 0.6603 63.9 84 0.685 0.895
Benzene 78.12 0.8765 0.812
n-C 100.21 0.6837 91.9 96 0.722 0.892
n-C 114.22 0.7025 116.7 107 0.745 0.890
n-C 128.26 0.7176 142.2 121 0.764 0.888
n-C 142.28 0.73 165.8 134 0.778 0.887
n-C 156.32 0.7402 187.2 147 0.789 0.886
n-C 170.34 0.7487 208.3 161 0.800 0.885
n-C 184.37 0.7564 227.2 175 0.811 0.884
n-C 198.39 0.7628 246.4 190 0.822 0.883
n-C 212.41 0.7685 266 206 0.832 0.883
n-C 226.45 0.7733 283 222 0.839 0.882
n-C 240.48 0.778 300 237 0.847 0.882
n-C 254.51 0.782 313 251 0.852 0.881
n-C 268.53 0.7855 325 263 0.857 0.881
n-C 282.56 0.7886 338 275 0.862 0.881
n-C 296.59 0.7919 351 291 0.867 0.880
n-C 310.61 0.7944 363 305 0.872 0.880
n-C 324.67 0.7969 375 318 0.877 0.880
n-C 338.67 0.7991 386 331 0.881 0.880
...