ASTM D2650-04

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D2650–04
Standard Test Method for
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Chemical Composition of Gases By Mass Spectrometry
This standard is issued under the fixed designation D2650; 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* D1137 Method for Analysis of Natural Gases and Related
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Types of Gaseous Mixtures by the Mass Spectrometer
1.1 This test method covers the quantitative analysis of
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D1145 Test Method for Sampling Natural Gas
gases containing specific combinations of the following com-
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D1247 Method of Sampling Manufactured Gas
ponents: hydrogen; hydrocarbons with up to six carbon atoms
D1265 Practice for Sampling Liquefied Petroleum (LP)
per molecule; carbon monoxide; carbon dioxide; mercaptans
Gases, Manual Method
with one or two carbon atoms per molecule; hydrogen sulfide;
D1302 MethodforAnalysisofCarburetedWaterGasbythe
and air (nitrogen, oxygen, and argon). This test method cannot
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Mass Spectrometer
be used for the determination of constituents present in
amounts less than 0.1 mole %. Dimethylbutanes are assumed
3. Terminology
absent unless specifically sought.
3.1 Definitions:
NOTE 1—Although experimental procedures described herein are uni-
3.1.1 base peak of a compound—the peak used as 100 % in
form, calculation procedures vary with application. The following influ-
computing the cracking pattern coefficient.
ences guide the selection of a particular calculation: qualitative mixture
3.1.2 cracked gases—hydrocarbon gases that contain unsat-
composition; minimum error due to components presumed absent; mini-
urates.
mum cross interference between known components; maximum sensitiv-
3.1.3 cracking pattern coeffıcient—the ratio of a peak at any
ity to known components; low frequency and complexity of calibration;
and type of computing machinery. m/e relative to its parent peak (or in some cases its base peak).
Because of these influences, a tabulation of calculation procedures
3.1.4 GLC—a gas-liquid chromatographic column that is
recommended for stated applications is presented in Section 12 (Table 1).
capable of separating the isomers of butenes, pentenes, hex-
NOTE 2—This test method was developed on Consolidated Electrody-
anes, and hexenes.
namics Corporation Type 103 Mass Spectrometers. Users of other
3.1.5 IR—infrared equipment capable of analyzing gases
instruments may have to modify operating parameters and the calibration
for the butene isomers.
procedure.
3.1.6 mass number or m/e value of an ion—the quotient of
1.2 This standard does not purport to address all of the
the mass of that ion (given in atomic mass units) and its
safety concerns, if any, associated with its use. It is the
positive charge (number of electrons lost during ionization).
responsibility of the user of this standard to establish appro-
3.1.7 parent peak of a compound—the peak at which the
priate safety and health practices and determine the applica-
m/e is equal to the sum of the atomic mass values for that
bility of regulatory limitations prior to use.
compound. This peak is sometimes used as 100 % in comput-
ing the cracking pattern coefficients.
2. Referenced Documents
3.1.8 partial pressure—the pressure of any component in
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2.1 ASTM Standards:
the inlet system before opening the expansion bottle to leak.
3.1.9 sensitivity—the height of any peak in the spectrum of
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the pure compound divided by the pressure prevailing in the
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee inlet system of the mass spectrometer immediately before
D02.04 on Hydrocarbon Analysis.
opening the expansion bottle to leak.
Current edition approved Nov. 1, 2004. Published November 2004. Originally
3.1.10 straight-run gases—hydrocarbon gases that do not
approved in 1967. Last previous edition approved in 1999 as D2650–99. DOI:
contain unsaturates.
10.1520/D2650-04.
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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
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Standards volume information, refer to the standard’s Document Summary page on Withdrawn. The last approved version of this historical standard is referenced
the ASTM website. on www.astm.org.
*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.
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D2650–04
TABLE 1 Calculation Procedures for Mass Spectrometer Gas Analysis
NOTE—Coding of calculation proc
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