ASTM D2504-88(2010)
(Test Method)Standard Test Method for Noncondensable Gases in C2 and Lighter Hydrocarbon Products by Gas Chromatography
Standard Test Method for Noncondensable Gases in C<sub>2</sub> and Lighter Hydrocarbon Products by Gas Chromatography
SIGNIFICANCE AND USE
The presence of trace amounts of hydrogen, oxygen, and carbon monoxide can have deleterious effects in certain processes using hydrocarbon products as feed stock. This test method is suitable for setting specifications, for use as an internal quality control tool and for use in development or research work.
SCOPE
1.1 This test method covers the determination of hydrogen, nitrogen, oxygen, and carbon monoxide in the parts per million volume (ppmv) range in C2 and lighter hydrocarbon products. This test method should be applicable to light hydrocarbons other than ethylene, but the test program did not include them.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.3 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 and health practices and determine the applicability of regulatory limitations prior to use. For some specific hazard statements, see the Annex A1.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D2504 − 88(Reapproved 2010)
Standard Test Method for
Noncondensable Gases in C and Lighter Hydrocarbon
Products by Gas Chromatography
This standard is issued under the fixed designation D2504; 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 concentration of the gases to be determined is calculated from
the recorded peak heights or peak areas.Argon can be used as
1.1 This test method covers the determination of hydrogen,
a carrier gas for the determination of hydrogen in concentra-
nitrogen, oxygen, and carbon monoxide in the parts per million
tions below 100 ppmv. Argon, if present in the sample,
volume (ppmv) range in C and lighter hydrocarbon products.
interferes with oxygen determination.
This test method should be applicable to light hydrocarbons
other than ethylene, but the test program did not include them.
4. Significance and Use
1.2 The values stated in SI units are to be regarded as the
4.1 Thepresenceoftraceamountsofhydrogen,oxygen,and
standard. The values given in parentheses are for information
carbon monoxide can have deleterious effects in certain pro-
only.
cesses using hydrocarbon products as feed stock. This test
1.3 This standard does not purport to address all of the
method is suitable for setting specifications, for use as an
safety concerns, if any, associated with its use. It is the
internal quality control tool and for use in development or
responsibility of the user of this standard to establish appro-
research work.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. For some specific
5. Apparatus
hazard statements, see the Annex A1.
5.1 Chromatograph—Any chromatographic instrument
2. Referenced Documents
havingeitherathermalconductivityorionizationdetectorwith
an overall sensitivity sufficient to detect 2 ppmv or less of the
2.1 ASTM Standards:
compounds listed in the scope, with a peak height of at least 2
D2505 Test Method for Ethylene, Other Hydrocarbons, and
mm without loss of resolution.
Carbon Dioxide in High-Purity Ethylene by Gas Chroma-
tography
5.2 Detectors—Thermal Conductivity—If a methanation re-
E260 Practice for Packed Column Gas Chromatography
actor is used, a flame ionization detector is also required. To
F307 Practice for Sampling Pressurized Gas for Gas Analy-
determine carbon monoxide with a flame ionization detector, a
sis
methanation reactor must be inserted between the column and
2.2 Other Standard:
the detector and hydrogen added as a reduction gas. Details on
Compressed GasAssociation Booklets G-4 and G-4.1 on the
the preparation and use of the reactor are given in Appendix
use of oxygen.
X1.
3. Summary of Test Method 5.3 Constant-Volume Gas Sampling Valve.
3.1 The sample is separated in a gas-solid chromatographic
5.4 Column—Any column or set of columns that is capable
system using molecular sieves as the solid adsorbent. The
of resolving the components listed in the scope can be used.
Copper, stainless steel, or aluminum tubing may be used. The
1 columns chosen must afford a resolution such that the depth of
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of the valleys ahead of the trace peak is no less than 50 % of the
Subcommittee D02.D0.02 on Ethylene.
trace peak height.
Current edition approved May 1, 2010. Published May 2010. Originally
E1
approved in 1966. Last previous edition approved in 2004 as D2504 – 88 (2004) .
5.5 Recorder—A recorder with a full-scale response of 2 s
DOI: 10.1520/D2504-88R10.
or less and a maximum rate of noise of 60.3 % of full scale.
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
5.6 Oven—The oven used for activating molecular sieves
Standards volume information, refer to the standard’s Document Summary page on
must be maintained at 260 to 288°C (500 to 550°F) and should
the ASTM website.
3 bedesignedsothatthegasesmaybedisplacedcontinuouslyby
Available from Compressed Gas Association (CGA), 4221 Walney Rd., 5th
Floor, Chantilly, VA 20151-2923, http://www.cganet.com. a stream of inert gas. The oven may be a thermostated piece of
Copyright ©ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959. United States
D2504 − 88 (2010)
1-in. pipe about 0.3 m (1 ft) in length. Electrical heating tapes erate the column in the oven in the same manner as described
or other means may be used for heating provided the heat is in 8.1 whenever the oxygen is not completely separated from
distributed uniformly. the nitrogen peak.
NOTE 1—The use of copper tubing is not recommended with samples
9. Calibration
containing acetylene as this could lead to the formation of potentially
9.1 Bring the equipment and column to equilibrium and
explosive copper acetylide.
maintain a constant carrier gas rate and temperature.
6. Reagents and Materials
NOTE 4—Carrier gas rates of 36 to 60 mL/min and temperatures of 50
to 60°C have been used successfully.
6.1 MolecularSieves,5A,13A,or13X—Anymeshsizescan
be used so long as sensitivity and resolution are maintained
9.2 Prepare at least three synthetic standard samples con-
(see Note 2). If a 40 to 60-mesh sieve size is desired, but is not
taining the compounds to be determined over the range of
available, it may be prepared as described in 8.1.
concentration desired in the products to be analyzed, using the
pure gases or the certified blend. For the preparation of the
6.2 Coconut Charcoal, 30 to 60-mesh sieve size (optional).
second, third, and following calibration samples it is always
NOTE 2—Columns that have been found to give the desired separation
preferable not to dilute the first sample.
include a 1-m by 3.175-mm outside diameter column of 100 to 120 mesh
5Amolecular sieve, a 3-m by 6.35-mm outside diameter column of 40 to
NOTE5—Syntheticstandardsamplesshouldbepreparedasdescribedin
60-mesh 5Asieve, and a 7.7-m by 6.35-mm outside diameter column with
Test Method D2505.
13A or 13X sieve in the first 7.4 m and charcoal in the 0.3 m.
9.3 Inject a known volume of one of the standard samples,
6.3 Gases for Calibration—Pure or research grade
using a minimum of 1 mL for detecting 2 ppmv.
hydrogen, oxygen, nitrogen, and carbon monoxide will be
NOTE 6—Use of a reverse-flow arrangement will facilitate removal of
needed to prepare synthetic standard samples as described in
heavier gases and decrease the elapsed time of analysis.
TestMethodD2505.(Warning—Flammablegases.Hazardous
9.4 Record all of the desired peaks on each of the synthetic
pressure. See Annexes A1.1 – A1.5.) (Warning—Flammable.
blends prepared.
Poison. Harmful if inhaled. Dangerous when exposed to flame.
SeeAnnex A1.5.) (Warning—Hazardous pressure. SeeAnnex
9.5 Prepare a chart for each compound, plotting the peak
A1.2.) Certified calibration blends are commercially available
height of the compound or peak area of the compound against
from numerous sources and can be used as the synthetic
the concentration of the compounds in ppmv. The peak area
standard samples.
can be determined by any method that meets the precision
requirements of Section 12. Methods found to be acceptable
6.4 Carrier Gases—Argon or helium.
include planimetering, integration (electronic or mechanical or
NOTE 3—Practice E260 contains information that will be helpful to
computer processing), and triangulation.
those using this test method.
10. Procedure
7. Sampling
10.1 Connect the sample cylinder containing a gaseous
7.1 Samples shall be supplied to the laboratory in high-
sample to the gas sample valve with a metal tube and allow the
pressure sample cylinders, obtained using the procedures
sample to flow from the sample tube for about ⁄2 min. at a rate
described in Practice F307 or similar methods.
of 70 to 100 mL/min.
10.2 Inject into the instrument the same volume of sample
8. Preparation of Apparatus
as used for calibration, (pressure of sample and calibration gas
8.1 Chromatographic Column Packing—Crush in a porce-
must be the same in the sample loop) and record the peak areas
lain mortar and sieve to 40 to 60-mesh size about 200 g of
or peak heights desired.
molecular sieves 5A in order to have enough for several
columns. All work of preparing molecular sieves and packing
11. Calculation
columns with this material shall be done rapidly, preferably
11.1 From the peak height or area of the compound in the
under a blanket of dry nitrogen in order to minimize moisture
sample, determine the moles per million of the compound
absorption. Heat the screened molecular sieves in an oven at
using the charts prepared in calibration.Atypical characteriza-
274 6 14°C (525 6 25°F) for 24 h purging with dry nitrogen
tion showing hydrogen, oxygen, and nitrogen in ethylene is
at a rate of about 5 mL/min during this time. The nitrogen rate
presented in Fig. 1.
is not critical and can be measured by any convenient means
such as an orifice meter, rotameter, manometer, etc. Do not use 12. Precision and Bias
a wet test meter.
12.1 The precision of this test method as determined by
8.2 ChromatographicColumn—Purge the metal tubing with statistical examination of interlaboratory results is as follows:
dry nitrogen. Insert a small amount of glass wool in the end. 12.1.1 Repeatability—The difference between successive
Fill rapidly with the screened and activated molecular sieves, test results, obtained by the same operator with the same
adding the latter in 1-g increments. Vibrate the column, adding apparatus under constant operating conditions on identical test
additional sieves during this period,
...
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