ASTM D2650-10(2015)

Standard Test Method for Chemical Composition of Gases by Mass Spectrometry

SIGNIFICANCE AND USE
5.1 A knowledge of the composition of refinery gases is useful in diagnosing the source of plant upsets, in determining the suitability of certain gas streams for use as fuel, or as feedstocks for polymerization and alkylation, and for monitoring the quality of commercial gases.
SCOPE
1.1 This test method covers the quantitative analysis of gases containing specific combinations of the following components: hydrogen; hydrocarbons with up to six carbon atoms per molecule; carbon monoxide; carbon dioxide; mercaptans with one or two carbon atoms per molecule; hydrogen sulfide; and air (nitrogen, oxygen, and argon). This test method cannot be used for the determination of constituents present in amounts less than 0.1 mole %. Dimethylbutanes are assumed absent unless specifically sought.
Note 1: Although experimental procedures described herein are uniform, calculation procedures vary with application. The following influences guide the selection of a particular calculation: qualitative mixture composition; minimum error due to components presumed absent; minimum cross interference between known components; maximum sensitivity to known components; low frequency and complexity of calibration; and type of computing machinery.
Because of these influences, a tabulation of calculation procedures recommended for stated applications is presented in Section 12 (Table 1).    
Serial No. . . . . . . . . . .  
7  
8  
9  
10  
11  
12  
13  
Name or Application  
Commercial
Propane  
Commercial
Butane  
BB Stream
(Cracked
Butanes)  
Dry Gas
Cracked
Fuel Gas  
Mixed Iso
and Normal
Butanes  
Reformer
Make-Up
Gas  
Unstabi-
lized Fuel
Gas  
Component  
O  
P  
M  
O  
P  
M  
OC  
PC  
M  
O  
P  
M  
O  
P  
M  
O  
P  
M  
OC  
PC  
M  
Hydrogen  
...  
...  
...  
...  
...  
...  
...  
...  
...  
15  
2  
M  
...  
...  
...  
10  
2  
M  
16  
2  
M  
Methane  
...  
...  
...  
...  
...  
...  
...  
...  
...  
14  
16  
M  
...  
...  
...  
9  
16  
M  
15  
16  
M  
EthyleneE  
7  
26  
M  
...  
...  
...  
...  
...  
...  
12  
26  
M  
...  
...  
...  
...  
...  
...  
13  
26  
M  
Ethane  
6  
30  
M  
...  
...  
...  
...  
...  
...  
11  
30  
M  
...  
...  
...  
7  
30  
M  
12  
30  
M  
Propene  
5  
42  
M  
7  
42  
M  
6  
42  
M  
10  
42  
M  
...  
...  
...  
...  
...  
...  
8  
42  
M  
Propane  
3  
44  
M  
4  
44  
M  
4  
44  
M  
7  
44  
M  
3  
44  
M  
5  
44  
M  
6  
44  
M  
Butadiene  
...  
...  
...  
...  
...  
...  
1  
54  
M  
3  
54  
M  
...  
...  
...  
...  
...  
...  
2  
54  
M  
Butene-1  
1  
56  
M  
1  
56  
M  
7  
41  
M  
1  
...  
...  
...  
...  
...  
...  
...  
...  
9  
41  
M  
Butene-2  
1  
56  
M  
1  
56  
M  
8  
56  
M  
1  
56  
M  
...  
...  
...  
...  
...  
...  
10  
56  
M  
Isobutene  
1F  
F  
M  
1  
F  
F  
9  
39  
M  
1  
F  
...  
4  
43  
M  
...  
...  
...  
11  
39  
M  
Isobutane  
4  
43  
M  
5  
43  
M  
5  
43  
M  
8  
43  
M  
1  
58  
M  
6  
43  
M  
7  
43  
M  
n-Butane  
2  
58  
M  
2  
58  
M  
2  
58  
M  
4  
58  
M  
...  
...  
...  
2  
58  
M  
3  
58  
M  
Pentenes  
...  
...  
...  
6  
70  
M  
G  
70  
U  
9  
70  
M  
...  
...  
...  
3  
57  
M  
...  
70  
U  
Isopentane  
...  
...  
...  
3  
57  
M  
3  
57  
M  
5  
57  
M  
2  
57  
M  
4  
72  
M  
4  
57  
M  
n-Pentane  
...  
...  
...  
...  
...  
...  
...  
...  
...  
6  
72  
M  
...  
...  
...  
...  
...  
...  
5  
72  
M  
Benzene  
...  
...  
...  
...  
...  ...

General Information

• Status: Historical
• Publication Date: 31-May-2015
• ICS: 71.040.40 - Chemical analysis
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.04.0M - Mass Spectrometry

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: D2650 − 10 (Reapproved 2015)
Standard Test Method for
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 Types of Gaseous Mixtures by the Mass Spectrometer
(Withdrawn 1981)
1.1 This test method covers the quantitative analysis of
D1247 Test Method for Sampling Manufactured Gas (With-
gases containing specific combinations of the following com-
drawn 1986)
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 Test Method for Analysis of Carbureted Water Gas
and air (nitrogen, oxygen, and argon). This test method cannot
by the Mass Spectrometer (Withdrawn 1967)
be used for the determination of constituents present in
2.2 American Petroleum Institute Standards:
amounts less than 0.1 mole %. Dimethylbutanes are assumed
MPMS 14.1 Collecting and Handling of Natural Gas
absent unless specifically sought.
NOTE 1—Although experimental procedures described herein are Samples for Custody Transfer
uniform, calculation procedures vary with application. The following
2.3 Gas Producers Association Standards:
influences guide the selection of a particular calculation: qualitative
GPA 2166 Obtaining Natural Gas Samples for Analysis by
mixture composition; minimum error due to components presumed
Gas Chromatography
absent; minimum cross interference between known components; maxi-
mum sensitivity to known components; low frequency and complexity of
calibration; and type of computing machinery.
3. Terminology
Because of these influences, a tabulation of calculation procedures
3.1 Definitions:
recommended for stated applications is presented in Section 12 (Table 1).
NOTE 2—This test method was developed on Consolidated Electrody-
3.1.1 base peak of a compound—the peak used as 100 % in
namics Corporation Type 103 Mass Spectrometers. Users of other
computing the cracking pattern coefficient.
instruments may have to modify operating parameters and the calibration
3.1.2 cracked gases—hydrocarbon gases that contain un-
procedure.
saturates.
1.2 The values stated in SI units are to be regarded as
3.1.3 cracking pattern coeffıcient—the ratio of a peak at any
standard. No other units of measurement are included in this
m/e relative to its parent peak (or in some cases its base peak).
standard.
3.1.4 GLC—a gas-liquid chromatographic column that is
1.3 This standard does not purport to address all of the
capable of separating the isomers of butenes, pentenes,
safety concerns, if any, associated with its use. It is the
hexanes, and hexenes.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
3.1.5 IR—infraredequipmentcapableofanalyzinggasesfor
bility of regulatory limitations prior to use.
the butene isomers.
3.1.6 mass number or m/e value of an ion—the quotient of
2. Referenced Documents
the mass of that ion (given in atomic mass units) and its
2.1 ASTM Standards: positive charge (number of electrons lost during ionization).
D1137 Method for Analysis of Natural Gases and Related
3.1.7 parent peak of a compound—thepeakatwhichthe m/e
is equal to the sum of the atomic mass values for that
compound. This peak is sometimes used as 100 % in comput-
This test method is under the jurisdiction of ASTM Committee D02 on
ing the cracking pattern coefficients.
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
Subcommittee D02.04.0M on Mass Spectroscopy.
CurrenteditionapprovedJune1,2015.PublishedJuly2015.Originallyapproved
in 1967. Last previous edition approved in 2010 as D2650 – 10. DOI: 10.1520/ The last approved version of this historical standard is referenced on
D2650-10R15. www.astm.org.
2 4
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from American Petroleum Institute (API), 1220 L. St., NW,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Washington, DC 20005-4070, http://www.api.org.
Standards volume information, refer to the standard’s Document Summary page on Available from Gas ProcessorsAssociation (GPA), 6526 E. 60th St., Tulsa, OK
the ASTM website. 74145, www.gpaglobal.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D2650 − 10 (2015)
TABLE 1 Calculation Procedures for Mass Spectrometer Gas Analysis
NOTE 1—Coding of calculation procedures is as follows:
O = Order peaks are used in the calculation expressed serially from 1 to n, n being the total number of components.
P= m/e of peak used and prefix, M, if monoisotopic.
M = Method of computation
U = Unicomponent Peak Method
M = Simultaneous equations where “a” identifies the particular set of equations if more than one is used.
a
C = Chemically removed.
Residual = m/e of peak suitable as an independent check on the method.
SerialNo. 123456
B
D1302
A
Reformer
D1137
Name or Application Carbureted H -C C ,C iC
2 6 3 4 4
Natural Gas
Gas
Water Gas
C C C C
Component O P M O P M O P MO P M O P MO P M
Hydrogen . . . 6 2 M 16 2 U 17 2 M 0 . . . . .
Methane 15 16 U 7 ⁄16 M 15 16 U 16 16 M 0 . . . . .
Ethylene 13 27 M2 12 27 M 13 26 U 15 26 M 0 . . . . .
Ethane 12 30 M2 8 30 M 12 30 U 13 30 M 0 . . . . .
Propene 10 42 M2 11 42 M 8 42 M2 12 42 M 6 42 M . . M
Propane 9 29 M2 9 29 M 3 44 M1 14 29 M 9 29 M 3 29 M
Butadiene . . . 9 . . 3 . . 10 54 M 9 . M . . M
Butene-1 8 56 M2 5 56 U 9 41 M2 8 56 M 8 41 M . . M
Butene-2 8 56 M2 5 56 U 10 55 M2 8 56 M 4 56 M . . M
Isobutene 8 56 M2 5 56 U 11 56 M2 8 56 M 5 39 M . . M
Isobutane 7 43 M2 5 . . 4 M43 M1 11 43 M 7 43 M 2 43 M
n-Butane 6 58 M2 4 58 U 5 58 M1 6 58 M 2 58 M 1 58 M
Pentenes . . . 3 70 U 2 70 U 9 55 M 3 70 M . . M
Isopentane . . . 3 . . 6 M57 M1 7 57 M 1 72 M . . .
n-Pentane 4 72 M2 2 72 U 7 72 M2 5 72 M . . . . . .
Benzene . . . 2 . . 7 . . 4 78 M . . . . . .
Hexanes . . . 2 . . 7 . . . . M . . . . . .
C cyclic paraffins . . . 2 . . 7 . . 3 84 M . . . . . .
Hexanes 5 57 M2 2 . . 1 71 U 2 86 M . . . . . .
Toluene . . . 2 . . 1 . . 1 92 M . . . . . .
Hydrogen sulfide 2 34 M1 2 . . 1 . . 21 34 M . . . . . .
Carbon dioxide 11 44 M2 10 44 M 1 . C 20 44 M . . . . . .
Carbon monoxide . . . 13 12 M 1 . C 18 28 M . . . . . .
Nitrogen 14 28 M2 14 14 M 14 28 U 19 14 M . . . . . .
Air 3 32 M1 1 32 U 14 . . 22 32 M 1 32 U . . .
DD
Helium 1 4 U 1 . . 14 . . . . . . . . .
SerialNo. 7 8 9 10 11 12 13
BB Stream Dry Gas Mixed Iso Reformer Unstabi-
Commercial Commercial
Name or Application (Cracked Cracked and Normal Make-Up lized Fuel
Propane Butane
Butanes) Fuel Gas Butanes Gas Gas
C C C C
Component O P M O P M O P MO P M O P MO P M O P M
Hydrogen . . . . . . . . . 15 2 M . . . 10 2 M 16 2 M
Methane . . . . . . . . . 14 16 M . . . 9 16 M 15 16 M
E
Ethylene 7 26 M . . . . . . 12 26 M . . . . . . 13 26 M
Ethane 6 30 M . . . . . . 11 30 M . . . 7 30 M 12 30 M
Propene 5 42 M 7 42 M 6 42 M 10 42 M . . . . . . 8 42 M
Propane 3 44 M 4 44 M 4 44 M 7 44 M 3 44 M 5 44 M 6 44 M
Butadiene . . . . . . 1 54 M 3 54 M . . . . . . 2 54 M
Butene-1 1 56 M 1 56 M 7 41 M 1 . . . . . . . . 9 41 M
Butene-2 1 56 M 1 56 M 8 56 M 1 56 M . . . . . . 10 56 M
FF FF F
Isobutene 1 M1 939 M 1 . 4 43 M . . . 11 39 M
Isobutane 4 43 M 5 43 M 5 43 M 8 43 M 1 58 M 6 43 M 7 43 M
n-Butane 2 58 M 2 58 M 2 58 M 4 58 M . . . 2 58 M 3 58 M
G
Pentenes . . . 6 70 M 70 U 9 70 M . . . 3 57 M . 70 U
Isopentane . . . 3 57 M 3 57 M 5 57 M 2 57 M 4 72 M 4 57 M
n-Pentane . . . . . . . . . 6 72 M . . . . . . 5 72 M
HH
Benzene . . . . . . . . . . . . . . . . . . D
HH
Hexanes . . . . . . . . . . . . . . . . . . D
HH
C cyclic paraffins . . . . . . . . . . . . . . . . . . D
HH
Hexanes . . . . . . . . . . . . . . . . . . D
HH
Toluene . . . . . . . . . . . . . . . . . . D
I II II
Hydrogen sulfide . . . . . . . . . . C . . . C C
I II II
Carbon dioxide . . . . . . . . . . C . . . C C
Carbon monoxide . . . . . . . . . 13 28 M . . . 8 28 M 14 28 M
Nitrogen . . . . . . . . . . . . . . . . . . . . .
Air . . . . . . . . . 2 32 M . . . 1 32 M 1 32 M
I II II
Acid Gases . . . . . . . . . . C . . . C C
E
Residual 8 27 M 8 27 M 10 27 M 16 14 M 5 27 M 11 14 M 17 14 M
E
Residual 9 29 M 9 29 M 11 29 M 17 15 M 6 29 M 12 15 M 18 15 M
E
Residual . . . . . . . . . 18 27 M . . . 13 27 M 19 27 M
E
Residual . . . . . . . . . 19 29 M . . . 14 29 M 20 29 M
D2650 − 10 (2015)
TABLE 1 Continued
SerialNo. 14 15 16
Name or Application H -C Cracked Gas H -C Straight Run Gas Light Refinery Gas
2 6 2 6
Component O P M O P M O P M
Hydrogen 1 2 M 1 2 M 20 2 U
Methane 2 16 M 2 16 M 17 16 M
Ethylene 4 26 M . . . 14 26 M
Ethane 7 30 M 5 30 M 13 30 M
Propene 11 42 M . . . 12 42 M
Propane 6 29 M 4 29 M 10 29 M
Butadiene 15 54 M . . . . . .
Butane-1 . . . . . . 11 56 M
Butene-2 16 56 M . . . . . .
Isobutene . . . . . . . . .
Isobutane 12 43 M 9 43 M 9 43 M
n-Butane 18 58 M 14 58 M 8 58 M
Pentenes 21 70 M . . . 15 70 M
Isopentane 17 57 M 13 57 M 7 57 M
n-Pentane 22 72 M 18 72 M 6 72 M
Benzene . . . 19 78 M 5 78 U
Hexanes 23 84 M . . . 4 84 U
C cyclic paraffins . . . 20 84 M . . .
Hexanes . . . 17 71 M 3 86 U
Toluene . . . 21 92 M . . .
Hydrogen sulfide 9 34 M 7 34 M 1 34 U
Carbon dioxide 13 44 M 10 44 M 16 44 U
Carbon monoxide . . . . . . 18 12 U
Nitrogen 5 28 M . . . 19 28 U
Air 8 32 M 6 32 M 2 32 U
Water 3 18 M 3 18 M . . .
Cyclobutane . . . 12 56 M . . .
Cyclopentene 20 67 M . . . . . .
Pentadienes 20 67 M . . . . . .
Cyclopentane . . . 16 70 M . . .
Methylmercaptan 14 48 M 11 48 M . . .
Ethylmercaptan 19 62 M 15 62 M . . .
Residual 41 10 41 M 8 41 M . . .
Residual 14 24 14 M 22 14 M . . .
A
Method D1137.
B
Method D1302.
C
The mass spectrometer analysis for isomeric butenes is far less accurate than for the other hydrocarbon components. The inaccuracies involved in the isomeric butene
analysisbymassspectrometerrangefrom1.0to4.0mole %,dependingupontheconcentration,ranges,andextentofdriftsininstrumentcalibrations.Theseinaccuracies
will range still higher when pentenes are present in larger than 0.5 % concentrations. See Analytical Chemistry, Vol 22, 1950, p. 991; Ibid, Vol 21, 1949, p. 547; and Ibid
, Vol 21, 1949, p. 572.
D
In Method 4, butylenes and pentenes spectra are composites based on typical GLC analyses. Hexene and hexane spectra are from appropriately corrected spectra of
representative fractions.
E
Residuals GroupsA: m/e 72, 58, 57, 44, 43; Group B: m/e 56, 42, 30, 29, 14.All GroupAresidual shall be 0.2 division or less with the residual of the largest peak also
being less than 0.3 % of its total peak height. All Group B residuals shall be less than 1 % of the peak height or 0.2 division, whichever is greater.
F
Butenes are grouped if they are less than 5 %.
G
If pentenes exceed 1 %, they are determined by other means and the spectrum removed from the poly spectrum.
H
Removed from sample by distillation.
I
Chemically removed.
3.1.8 partial pressure—the pressure of any component in spectrum obtained is resolved into individual constituents by
the inlet system before opening the expansion bottle to leak. means of simultaneous equations derived from the mass
spectra of the pure compounds.
3.1.9 sensitivity—the height of any peak in the spectrum of
the pure compound divided by the pressure prevailing in the
5. Significance and Use
inlet system of the mass spectrometer immediately before
opening the expansion bottle to leak. 5.1 A knowledge of the composition of refinery gases is
useful in diagnosing the source of plant upsets, in determining
3.1.10 straight-run gases—hydrocarbon gases that do not
the suitability of certain gas streams for use as fuel, or as
contain unsaturates.
feedstocks for polymerization and alkylation, and for monitor-
4. Summary of Test Method ing the quality of commercial gases.
4.1 The molecular species which make up a gaseous mix-
6. Interferences
ture are dissociated and ionized by electron bombardment.The
positive ions of the different masses thus formed are acceler- 6.1 In setting up an analysis, it is possible that a constituent
ated in an electrostatic field and separated in a magnetic field. was ignored.Also, an impure calibration may have been used.
The abundance of each mass present is recorded. The mixture The spectrum calculated from the composition found is to,
D2650 − 10 (2015)
therefore, be compared with the observed spectrum of the ionization chamber or by other techniques commonly used by
mixture at masses independent of the original calculation. the laboratory. In any case, the three 43/58 and 43/29 ratios
Differences so computed, called residuals, should as a general must agree within 0.8 % and the three butane sensitivities
rule be less than 1 % of the original mixture peak for an within 1 %. The two hydrogen sensitivities must agree within
acceptable analysis. Masses suitable for this calculation are 1.5 %.Astandard gas sample can also be used as an additional
tabulated with each calculation procedure. check.
NOTE 3—Another strategy employed to reduce interferences and
10.
...

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: D2650 − 10 D2650 − 10 (Reapproved 2015)
Standard Test Method for
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*Scope
1.1 This test method covers the quantitative analysis of gases containing specific combinations of the following components:
hydrogen; hydrocarbons with up to six carbon atoms per molecule; carbon monoxide; carbon dioxide; mercaptans with one or two
carbon atoms per molecule; hydrogen sulfide; and air (nitrogen, oxygen, and argon). This test method cannot be used for the
determination of constituents present in amounts less than 0.1 mole %. Dimethylbutanes are assumed absent unless specifically
sought.
NOTE 1—Although experimental procedures described herein are uniform, calculation procedures vary with application. The following influences guide
the selection of a particular calculation: qualitative mixture composition; minimum error due to components presumed absent; minimum cross interference
between known components; maximum sensitivity to known components; low frequency and complexity of calibration; and type of computing machinery.
Because of these influences, a tabulation of calculation procedures recommended for stated applications is presented in Section 12 (Table 1).
NOTE 1—Although experimental procedures described herein are uniform, calculation procedures vary with application. The following influences guide
the selection of a particular calculation: qualitative mixture composition; minimum error due to components presumed absent; minimum cross interference
between known components; maximum sensitivity to known components; low frequency and complexity of calibration; and type of computing machinery.
Because of these influences, a tabulation of calculation procedures recommended for stated applications is presented in Section 12 (Table 1).
NOTE 2—This test method was developed on Consolidated Electrodynamics Corporation Type 103 Mass Spectrometers. Users of other instruments may
have to modify operating parameters and the calibration procedure.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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.
2. Referenced Documents
2.1 ASTM Standards:
D1137 Method for Analysis of Natural Gases and Related Types of Gaseous Mixtures by the Mass Spectrometer (Withdrawn
1981)
D1247 Test Method for Sampling Manufactured Gas (Withdrawn 1986)
D1265 Practice for Sampling Liquefied Petroleum (LP) Gases, Manual Method
D1302 Test Method for Analysis of Carbureted Water Gas by the Mass Spectrometer (Withdrawn 1967)
2.2 American Petroleum Institute Standards:
MPMS 14.1 Collecting and Handling of Natural Gas Samples for Custody Transfer
2.3 Gas Producers Association Standards:
GPA 2166 Obtaining Natural Gas Samples for Analysis by Gas Chromatography
3. Terminology
3.1 Definitions:
3.1.1 base peak of a compound—the peak used as 100 % in computing the cracking pattern coefficient.
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
D02.04.0M on Mass Spectroscopy.
Current edition approved May 1, 2010June 1, 2015. Published July 2010July 2015. Originally approved in 1967. Last previous edition approved in 20042010 as
D2650D2650 – 10.–04. DOI: 10.1520/D2650-10.10.1520/D2650-10R15.
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.
The last approved version of this historical standard is referenced on www.astm.org.
Available from American Petroleum Institute (API), 1220 L. St., NW, Washington, DC 20005-4070, http://www.api.org.
Available from Gas Processors Association (GPA), 6526 E. 60th St., Tulsa, OK 74145, www.gpaglobal.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
D2650 − 10 (2015)
TABLE 1 Calculation Procedures for Mass Spectrometer Gas Analysis
NOTE 1—Coding of calculation procedures is as follows:
O = Order peaks are used in the calculation expressed serially from 1 to n,n being the total number of components.
P = m/e of peak used and prefix, M, if monoisotopic.
M = Method of computation
U = Unicomponent Peak Method
M = Simultaneous equations where “a” identifies the particular set of equations if more than one is used.
a
C = Chemically removed.
Residual = m/e of peak suitable as an independent check on the method.
Serial No. . . . . . . . . . . 1 2 3 4 5 6
B
D1302
A
Reformer
D1137
Name or Application Carbureted H -C C ,C iC
2 6 3 4 4
Natural Gas Gas
Water Gas
C C C C
Component O P M O P M O P M O P M O P M O P M
Hydrogen . . . 6 2 M 16 2 U 17 2 M 0 . . . . .
Methane 15 16 U 7 ⁄16 M 15 16 U 16 16 M 0 . . . . .
Ethylene 13 27 M2 12 27 M 13 26 U 15 26 M 0 . . . . .
Ethane 12 30 M2 8 30 M 12 30 U 13 30 M 0 . . . . .
Propene 10 42 M2 11 42 M 8 42 M2 12 42 M 6 42 M . . M
Propane 9 29 M2 9 29 M 3 44 M1 14 29 M 9 29 M 3 29 M
Butadiene . . . 9 . . 3 . . 10 54 M 9 . M . . M
Butene-1 8 56 M2 5 56 U 9 41 M2 8 56 M 8 41 M . . M
Butene-2 8 56 M2 5 56 U 10 55 M2 8 56 M 4 56 M . . M
Isobutene 8 56 M2 5 56 U 11 56 M2 8 56 M 5 39 M . . M
Isobutane 7 43 M2 5 . . 4 M43 M1 11 43 M 7 43 M 2 43 M
n-Butane 6 58 M2 4 58 U 5 58 M1 6 58 M 2 58 M 1 58 M
Pentenes . . . 3 70 U 2 70 U 9 55 M 3 70 M . . M
Isopentane . . . 3 . . 6 M57 M1 7 57 M 1 72 M . . .
n-Pentane 4 72 M2 2 72 U 7 72 M2 5 72 M . . . . . .
Benzene . . . 2 . . 7 . . 4 78 M . . . . . .
Hexanes . . . 2 . . 7 . . . . M . . . . . .
C cyclic paraffins . . . 2 . . 7 . . 3 84 M . . . . . .
Hexanes 5 57 M2 2 . . 1 71 U 2 86 M . . . . . .
Toluene . . . 2 . . 1 . . 1 92 M . . . . . .
Hydrogen sulfide 2 34 M1 2 . . 1 . . 21 34 M . . . . . .
Carbon dioxide 11 44 M2 10 44 M 1 . C 20 44 M . . . . . .
Carbon monoxide . . . 13 12 M 1 . C 18 28 M . . . . . .
Nitrogen 14 28 M2 14 14 M 14 28 U 19 14 M . . . . . .
Air 3 32 M1 1 32 U 14 . . 22 32 M 1 32 U . . .
D D
Helium 1 4 U 1 . . 14 . . . . . . . . .
Serial No. . . . . . . . . . . 7 8 9 10 11 12 13
BB Stream Dry Gas Mixed Iso Reformer Unstabi-
Commercial Commercial
Name or Application (Cracked Cracked and Normal Make-Up lized Fuel
Propane Butane
Butanes) Fuel Gas Butanes Gas Gas
C C C C
Component O P M O P M O P M O P M O P M O P M O P M
Hydrogen . . . . . . . . . 15 2 M . . . 10 2 M 16 2 M
Methane . . . . . . . . . 14 16 M . . . 9 16 M 15 16 M
E
Ethylene 7 26 M . . . . . . 12 26 M . . . . . . 13 26 M
Ethane 6 30 M . . . . . . 11 30 M . . . 7 30 M 12 30 M
Propene 5 42 M 7 42 M 6 42 M 10 42 M . . . . . . 8 42 M
Propane 3 44 M 4 44 M 4 44 M 7 44 M 3 44 M 5 44 M 6 44 M
Butadiene . . . . . . 1 54 M 3 54 M . . . . . . 2 54 M
Butene-1 1 56 M 1 56 M 7 41 M 1 . . . . . . . . 9 41 M
Butene-2 1 56 M 1 56 M 8 56 M 1 56 M . . . . . . 10 56 M
F F F F F
Isobutene 1 M 1 9 39 M 1 . 4 43 M . . . 11 39 M
Isobutane 4 43 M 5 43 M 5 43 M 8 43 M 1 58 M 6 43 M 7 43 M
n-Butane 2 58 M 2 58 M 2 58 M 4 58 M . . . 2 58 M 3 58 M
G
Pentenes . . . 6 70 M 70 U 9 70 M . . . 3 57 M . 70 U
Isopentane . . . 3 57 M 3 57 M 5 57 M 2 57 M 4 72 M 4 57 M
n-Pentane . . . . . . . . . 6 72 M . . . . . . 5 72 M
H H
Benzene . . . . . . . . . . . . . . . . . . D
H H
Hexanes . . . . . . . . . . . . . . . . . . D
H H
C cyclic paraffins . . . . . . . . . . . . . . . . . . D
H H
Hexanes . . . . . . . . . . . . . . . . . . D
H H
Toluene . . . . . . . . . . . . . . . . . . D
I I I I I
Hydrogen sulfide . . . . . . . . . . C . . . C C
I I I I I
Carbon dioxide . . . . . . . . . . C . . . C C
Carbon monoxide . . . . . . . . . 13 28 M . . . 8 28 M 14 28 M
Nitrogen . . . . . . . . . . . . . . . . . . . . .
Air . . . . . . . . . 2 32 M . . . 1 32 M 1 32 M
I I I I I
Acid Gases . . . . . . . . . . C . . . C C
E
Residual 8 27 M 8 27 M 10 27 M 16 14 M 5 27 M 11 14 M 17 14 M
E
Residual 9 29 M 9 29 M 11 29 M 17 15 M 6 29 M 12 15 M 18 15 M
E
Residual . . . . . . . . . 18 27 M . . . 13 27 M 19 27 M
E
Residual . . . . . . . . . 19 29 M . . . 14 29 M 20 29 M
D2650 − 10 (2015)
TABLE 1 Continued
Serial No. . . . . . . . . . . 14 15 16
Name or Application H -C Cracked Gas H -C Straight Run Gas Light Refinery Gas
2 6 2 6
Component O P M O P M O P M
Hydrogen 1 2 M 1 2 M 20 2 U
Methane 2 16 M 2 16 M 17 16 M
Ethylene 4 26 M . . . 14 26 M
Ethane 7 30 M 5 30 M 13 30 M
Propene 11 42 M . . . 12 42 M
Propane 6 29 M 4 29 M 10 29 M
Butadiene 15 54 M . . . . . .
Butane-1 . . . . . . 11 56 M
Butene-2 16 56 M . . . . . .
Isobutene . . . . . . . . .
Isobutane 12 43 M 9 43 M 9 43 M
n-Butane 18 58 M 14 58 M 8 58 M
Pentenes 21 70 M . . . 15 70 M
Isopentane 17 57 M 13 57 M 7 57 M
n-Pentane 22 72 M 18 72 M 6 72 M
Benzene . . . 19 78 M 5 78 U
Hexanes 23 84 M . . . 4 84 U
C cyclic paraffins . . . 20 84 M . . .
Hexanes . . . 17 71 M 3 86 U
Toluene . . . 21 92 M . . .
Hydrogen sulfide 9 34 M 7 34 M 1 34 U
Carbon dioxide 13 44 M 10 44 M 16 44 U
Carbon monoxide . . . . . . 18 12 U
Nitrogen 5 28 M . . . 19 28 U
Air 8 32 M 6 32 M 2 32 U
Water 3 18 M 3 18 M . . .
Cyclobutane . . . 12 56 M . . .
Cyclopentene 20 67 M . . . . . .
Pentadienes 20 67 M . . . . . .
Cyclopentane . . . 16 70 M . . .
Methylmercaptan 14 48 M 11 48 M . . .
Ethylmercaptan 19 62 M 15 62 M . . .
Residual 41 10 41 M 8 41 M . . .
Residual 14 24 14 M 22 14 M . . .
A
Method D1137.
B
Method D1302.
C
The mass spectrometer analysis for isomeric butenes is far less accurate than for the other hydrocarbon components. The inaccuracies involved in the isomeric butene
analysis by mass spectrometer range from 1.0 to 4.0 mole %, depending upon the concentration, ranges, and extent of drifts in instrument calibrations. These inaccuracies
will range still higher when pentenes are present in larger than 0.5 % concentrations. See Analytical Chemistry, Vol 22, 1950, p. 991; Ibid, Vol 21, 1949, p. 547; and Ibid
, Vol 21, 1949, p. 572.
D
In Method 4, butylenes and pentenes spectra are composites based on typical GLC analyses. Hexene and hexane spectra are from appropriately corrected spectra of
representative fractions.
E
Residuals Groups A: m/e 72, 58, 57, 44, 43; Group B: m/e 56, 42, 30, 29, 14. All Group A residual shall be 0.2 division or less with the residual of the largest peak also
being less than 0.3 % of its total peak height. All Group B residuals shall be less than 1 % of the peak height or 0.2 division, whichever is greater.
F
Butenes are grouped if they are less than 5 %.
G
If pentenes exceed 1 %, they are determined by other means and the spectrum removed from the poly spectrum.
H
Removed from sample by distillation.
I
Chemically removed.
3.1.2 cracked gases—hydrocarbon gases that contain unsaturates.
3.1.3 cracking pattern coeffıcient—the ratio of a peak at any m/e relative to its parent peak (or in some cases its base peak).
3.1.4 GLC—a gas-liquid chromatographic column that is capable of separating the isomers of butenes, pentenes, hexanes, and
hexenes.
3.1.5 IR—infrared equipment capable of analyzing gases for the butene isomers.
3.1.6 mass number or m/e value of an ion—the quotient of the mass of that ion (given in atomic mass units) and its positive
charge (number of electrons lost during ionization).
3.1.7 parent peak of a compound—the peak at which the m/e is equal to the sum of the atomic mass values for that compound.
This peak is sometimes used as 100 % in computing the cracking pattern coefficients.
3.1.8 partial pressure—the pressure of any component in the inlet system before opening the expansion bottle to leak.
3.1.9 sensitivity—the height of any peak in the spectrum of the pure compound divided by the pressure prevailing in the inlet
system of the mass spectrometer immediately before opening the expansion bottle to leak.
3.1.10 straight-run gases—hydrocarbon gases that do not contain unsaturates.
D2650 − 10 (2015)
4. Summary of Test Method
4.1 The molecular species which make up a gaseous mixture are dissociated and ionized by electron bombardment. The positive
ions of the different masses thus formed are accelerated in an electrostatic field and separated in a magnetic field. The abundance
of each mass present is recorded. The mixture spectrum obtained is resolved into individual constituents by means of simultaneous
equations derived from the mass spectra of the pure compounds.
5. Significance and Use
5.1 A knowledge of the composition of refinery gases is useful in diagnosing the source of plant upsets, in determi
...