ASTM D6159-97(2007)
(Test Method)Standard Test Method for Determination of Hydrocarbon Impurities in Ethylene by Gas Chromatography
Standard Test Method for Determination of Hydrocarbon Impurities in Ethylene by Gas Chromatography
SIGNIFICANCE AND USE
High-purity ethylene is required as a feedstock for some manufacturing processes and the presence of trace amounts of certain hydrocarbon impurities can have deleterious effects. This test method is suitable for setting specifications, for use as an internal quality control tool, and for use in development or research work.
This test method does not detect such impurities as H2O, CO, CO2, and alcohols that may be present in the sample. Hydrocarbons higher than n-decane cannot be analyzed by this test method, if present in the sample. Test Method D 2504 addresses the analysis of noncondensable gases and Test Method D 2505 addresses the analysis of CO2. Guide D 5234 describes all potential impurities present in ethylene. These standards should be consulted when determining the total concentration of impurities in ethylene.
SCOPE
1.1 This test method covers the determination of methane, ethane, propane, propene, acetylene, iso-butane, propadiene, butane, trans-2-butene, butene-1, isobutene, cis-2-butene, methyl acetylene and 1,3-butadiene in high-purity ethylene. The purity of the ethylene can be calculated by subtracting the total percentage of all impurities from 100.00 %. Since this test method does not determine all possible impurities such as CO, CO2, H2O, alcohols, nitrogen oxides, and carbonyl sulfide, as well as hydrocarbons higher than decane, additional tests may be necessary to fully characterize the ethylene sample.
1.2 Data are reported in this test method as ppmV (parts per million by volume). This test method was evaluated in an interlaboratory cooperative study in the concentration range of 4 to 340 ppmV (2 to 204 mg/kg). The participants in the interlaboratory cooperative study reported the data in non-SI units. Wherever possible, SI units are included.
1.3 This standard dose 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
Relations
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: D6159 − 97(Reapproved 2007)
Standard Test Method for
Determination of Hydrocarbon Impurities in Ethylene by Gas
Chromatography
This standard is issued under the fixed designation D6159; 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 3. Summary of Test Method
3.1 Agaseous ethylene sample is analyzed as received. The
1.1 This test method covers the determination of methane,
ethane, propane, propene, acetylene, iso-butane, propadiene, gaseous sample is injected into a capillary gas chromatograph.
A split-injector may or may not be used. The gas chromato-
butane, trans-2-butene, butene-1, isobutene, cis-2-butene,
methyl acetylene and 1,3-butadiene in high-purity ethylene. graph is provided with a 6–port sampling valve and two wide
bore capillary columns connected in series. These columns are
The purity of the ethylene can be calculated by subtracting the
total percentage of all impurities from 100.00 %. Since this test a dimethyl silicone column and a (porous layer open tubular
column (PLOT)Al O /KCl column. Aflame ionization detec-
method does not determine all possible impurities such as CO,
2 3
CO,H O, alcohols, nitrogen oxides, and carbonyl sulfide, as tor is used for detection. The integrated detector signal (peak
2 2
areas) are corrected for detector response. The hydrocarbon
well as hydrocarbons higher than decane, additional tests may
be necessary to fully characterize the ethylene sample. impurities are determined and the total impurities are used to
determine the ethylene content.
1.2 Data are reported in this test method as ppmV (parts per
million by volume). This test method was evaluated in an
4. Significance and Use
interlaboratory cooperative study in the concentration range of
4.1 High-purity ethylene is required as a feedstock for some
4 to 340 ppmV (2 to 204 mg/kg). The participants in the
manufacturing processes and the presence of trace amounts of
interlaboratory cooperative study reported the data in non-SI
certain hydrocarbon impurities can have deleterious effects.
units. Wherever possible, SI units are included.
This test method is suitable for setting specifications, for use as
1.3 This standard dose not purport to address all of the
an internal quality control tool, and for use in development or
safety concerns, if any, associated with its use. It is the
research work.
responsibility of the user of this standard to establish appro-
4.2 ThistestmethoddoesnotdetectsuchimpuritiesasH O,
priate safety and health practices and determine the applica-
CO, CO , and alcohols that may be present in the sample.
bility of regulatory limitations prior to use. 2
Hydrocarbons higher than n-decane cannot be analyzed by this
test method, if present in the sample. Test Method D2504
2. Referenced Documents
addresses the analysis of noncondensable gases and Test
2.1 ASTM Standards:
Method D2505 addresses the analysis of CO . Guide D5234
D2504 Test Method for Noncondensable Gases in C and
describes all potential impurities present in ethylene. These
Lighter Hydrocarbon Products by Gas Chromatography
standards should be consulted when determining the total
D2505 Test Method for Ethylene, Other Hydrocarbons, and
concentration of impurities in ethylene.
Carbon Dioxide in High-Purity Ethylene by Gas Chroma-
tography
5. Apparatus
D5234 Guide for Analysis of Ethylene Product
5.1 Gas Chromatograph (GC), a gas chromatographic in-
strument provided with a temperature programmable column
ovenandaflameionizationdetector(FID).Regulatethecarrier
This test method is under the jurisdiction of ASTM Committee D02 on
gas by pressure control.
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee
5.2 Detector—Use a flame ionization detector (FID) having
D02.D0.02 on Ethylene.
Current edition approved Nov. 1, 2007. Published January 2008. Originally
asensitivityofapproximately2.0ppmV(1.2mg/kg)orlessfor
approved in 1997. Last previous edition approved in 2002 as D6159–97(2002).
the compounds listed in 1.1. An FID was exclusively used in
DOI: 10.1520/D6159-97R07.
the interlaboratory cooperative study.
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. This column is supplied by major column manufacturers.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6159 − 97 (2007)
FIG. 1 Valve Off – Sample Loading
FIG. 2 Valve On – Injection
5.3 Column Temperature Programmer —The chromato-
graph shall be capable of linear programmed temperature
operation over a range sufficient for separation of the compo-
nents of interest. Section 8 lists the recommended operating
conditions. The programming rate shall be sufficiently repro-
ducible to obtain retention repeatability of 0.05 min (3 s)
throughout the scope of this analysis.
5.4 Columns—Couple the two columns in series with either
aglasspresstightconnectororamini-connectorequippedwith
graphite ferrules.
5.4.1 Column 1, 50 m, 0.53 mm inside diameter (ID) KCl
deactivatedAl O PLOT column. Relative retention is depen-
2 3
FIG. 3 Valve Off – Sample Loading
dent on the deactivation method of the column. Other deacti-
vated Al O plot columns using sulfates as the deactivating
2 3
agent were also used in the interlaboratory comparison.
5.4.2 Column 2, 30 m, 0.53 mm ID, 5µm film thickness
methyl silicone. This column improves the separation of
methyl acetylene, iso-pentane, and n-pentane.
5.5 Sample Inlet System—Two injection modes were used
for the interlaboratory cooperative study.
5.5.1 A gas sampling valve placed in an unheated zone of
the gas chromatograph injecting the sample directly into the
column.
5.5.2 A gas sampling valve placed in an unheated zone of
the gas chromatograph in conjunction with a splitter injector
heated with a variable temperature control.
5.6 Gas Sampling Valve and Injection System—Use a 6-port
FIG. 4 Valve On – Injection
valve provided with ⁄16 in. fittings as the sample injection
system.AtypicalvalvearrangementisshowninFig.1andFig.
5.7 Data Acquisition System—Use any integrator or com-
2. Use a 10–60µL loop as shown in Fig. 1. Use good valve
puterized data acquisition system for peak area integration, as
maintenance techniques to avoid such problems as dead
well as for recording the chromatographic trace.
volumes,coldspots,longconnections,andnon-uniformheated
zones. The preferred carrier gas arrangement for sample
6. Reagent Materials
introduction is pressure regulation. Use a 6-port valve in
conjunction with a splitter injector. A typical arrangement is 6.1 Standard Mixture—Use a gravimetrically blended gas
shown in Fig. 3 and Fig. 4. Use split ratios of 50:1 to 100:1 at standard containing levels of 2 to 204 mg/kg (4 to 340 ppmV)
temperatures of 150°C to 200°C. Loop sizes of 200–500µL of each of the trace components listed in Table 1 to calibrate
were used in the interlaboratory study. When using a splitter it the detector’s response. The standard gas mixture shall be
isimportanttochecklinearityofthesplitter.Injectthestandard prepared gravimetrically from known raw materials, and cross
blend at 50:1, 75:1, and 100:1 split ratios. Check the response contaminants shall be taken into account. The mixtures should
factorsasdeterminedin9.1,andthefactorsshallnotvarymore be certified analytically such that the gravimetric and analyti-
than 3 %. cally derived values agree to an acceptable tolerance; that is 6
D6159 − 97 (2007)
TABLE 1 Typical Compounds and Retention Times for Common
Final time: 15 min.
A
Hydrocarbon Impurities in Ethylene
Carrier Gas
Components Retention Time, min
Helium at 6 to 8 mL/min
Methane 7.02
Injection System with Splitter
Ethane 8.12
Ethene 9.00
Sample valve loop volume = 200–500µl
Propane 12.41
Sample valve temperature = 35° to 45°C
Propene 16.93
Splitter temperature = 150° to 200°C
Ethyne 19.52
Isobutane 19.76
Split ratio = 50:1
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.