ASTM D5504-01(2006)
(Test Method)Standard Test Method for Determination of Sulfur Compounds in Natural Gas and Gaseous Fuels by Gas Chromatography and Chemiluminescence
Standard Test Method for Determination of Sulfur Compounds in Natural Gas and Gaseous Fuels by Gas Chromatography and Chemiluminescence
SIGNIFICANCE AND USE
Many sources of natural and petroleum gases contain sulfur compounds that are odorous, corrosive, and poisonous to catalysts used in gaseous fuel processing.
Low ppm amounts of sulfur odorants are added to natural gas and LP gases for safety purposes. Some odorants are unstable and react to form compounds having lower odor thresholds. Quantitative analysis of these odorized gases ensures that odorant injection equipment is performing to specification.
Although not intended for application to gases other than natural gas and related fuels, this test method has been successfully applied to fuel type gases including refinery, landfill, cogeneration, and sewage digester gas. Refinery, landfill, sewage digester and other related fuel type gases inherently contain volatile sulfur compounds that are subject to federal, state, or local control. The methane fraction of these fuel type gases are occasionally sold to distributors of natural gas. For these reasons, both regulatory agencies and production and distribution facilities may require the accurate determination of sulfur to satisfy regulatory, production or distribution requirements. Fuel gases are also used in energy production or are converted to new products using catalysts that are poisoned by excessive sulfur in the feed gas. Industry frequently requires measurement of sulfur in these fuel type gases to protect their catalyst investments.
Analytical Methods—Gas chromatography (GC) is commonly used in the determination of fixed gas and organic composition of natural gas (Test Method D 1945). Other standard ASTM methods for the analysis of sulfur in fuel gases include Test Methods D 1072 and D 4468 for total sulfur and Test Methods D 4010 and D 4884 for hydrogen sulfide.
SCOPE
1.1 This test method is primarily for the determination of speciated volatile sulfur-containing compounds in high methane content gaseous fuels such as natural gas. It has been successfully applied to other types of gaseous samples including air, digester, landfill, and refinery fuel gas. The detection range for sulfur compounds, reported as picograms sulfur, is ten (10) to one million (1 000 000). This is equivalent to 0.01 to 1 000 mg/m3, based upon the analysis of a 1 cc sample.
1.2 This test method does not purport to identify all sulfur species in a sample. Only compounds that are eluted through the selected column under the chromatographic conditions chosen are determined. The detector response to sulfur is equimolar for all sulfur compounds within the scope () of this test method. Thus, unidentified compounds are determined with equal precision to that of identified substances. Total sulfur content is determined from the total of individually quantified components.
1.3 The values stated in SI units are standard. The values stated in inch-pound units are for information only.
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.
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:D5504–01 (Reapproved 2006)
Standard Test Method for
Determination of Sulfur Compounds in Natural Gas and
Gaseous Fuels by Gas Chromatography and
Chemiluminescence
This standard is issued under the fixed designation D5504; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope D1072 Test Method for Total Sulfur in Fuel Gases by
Combustion and Barium Chloride Titration
1.1 This test method is primarily for the determination of
D1945 Test Method for Analysis of Natural Gas by Gas
speciated volatile sulfur-containing compounds in high meth-
Chromatography
ane content gaseous fuels such as natural gas. It has been
D3609 Practice for Calibration Techniques Using Perme-
successfully applied to other types of gaseous samples includ-
ation Tubes
ing air, digester, landfill, and refinery fuel gas. The detection
D4468 Test Method for Total Sulfur in Gaseous Fuels by
range for sulfur compounds, reported as picograms sulfur, is
Hydrogenolysis and Rateometric Colorimetry
ten (10) to one million (1 000 000). This is equivalent to 0.01
E594 Practice forTesting Flame Ionization Detectors Used
to 1 000 mg/m , based upon the analysis ofa1cc sample.
in Gas or Supercritical Fluid Chromatography
1.2 This test method does not purport to identify all sulfur
species in a sample. Only compounds that are eluted through
3. Summary of Test Method
the selected column under the chromatographic conditions
3.1 The analysis of gaseous sulfur compounds is challeng-
chosen are determined. The detector response to sulfur is
ing due to the reactivity of these substances. They are difficult
equimolar for all sulfur compounds within the scope (1.1)of
tosampleandanalyze.Ideally,analysisisperformedon-siteto
thistestmethod.Thus,unidentifiedcompoundsaredetermined
eliminatesampledeteriorationasafactorinanalysis.Sampling
with equal precision to that of identified substances. Total
must be performed using non-reactive containers, such as
sulfur content is determined from the total of individually
Silcosteelt lined vessels, Tedlar bags with polypropylene
quantified components.
fittingsortheequivalent.Tedlarbagsamplesrequireprotection
1.3 The values stated in SI units are standard. The values
from light and heat. Laboratory equipment must be inert or
stated in inch-pound units are for information only.
passivated to ensure reliable results.
1.4 This standard does not purport to address all of the
3.2 A one cc (mL) sample is injected into a gas chromato-
safety concerns, if any, associated with its use. It is the
graphwhereitiselutedthroughamegabore,thickfilm,methyl
responsibility of the user of this standard to establish appro-
siliconeliquidphase,opentubularpartitioningcolumnorother
priate safety and health practices and determine the applica-
suitable column, and separated into its individual constituents.
bility of regulatory limitations prior to use.
3.3 Sulfur Chemiluminescence Detection—As sulfur com-
2. Referenced Documents pounds elute from the gas chromatographic column, they are
2 processed in a flame ionization detector (FID) or a heated
2.1 ASTM Standards:
combustionzone.Theproductsarecollectedandtransferredto
a sulfur chemiluminescence detector (SCD). This technique
providesasensitive,selective,linearresponsetovolatilesulfur
ThistestmethodisunderthejurisdictionofASTMCommitteeD03onGaseous
compoundsandmaybeusedwhilecollectinghydrocarbonand
Fuels and is the direct responsibility of Subcommittee D03.05 on Determination of
fixed gas data from a FID.
Special Constituents of Gaseous Fuels.
3.3.1 Detectors in Series with a SCD—A SCD can fre-
CurrenteditionapprovedJune1,2006.PublishedJuly2006.Originallyapproved
in 1994. Last previous edition approved in 2001 as D5504–01.
quently be used in series with other fixed gas and hydrocarbon
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
detectors. However, regulatory bodies may question detector
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
compatibility and require demonstration of equivalence be-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. tween a SCD in a multi-detector system and a SCD operated
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D5504–01 (2006)
usingaFIDorcombustionzone.TheuserisreferredtoUSEPA structed of inert material and evaluated frequently for compat-
Method 301 for an example of a general equivalence proce- ibility with trace quantities of reactive sulfur compounds.
dure.
5.1.2 Carrier and Detector Gas Control—Constant flow
3.3.2 Alternative Detectors—This test method is written for
controlofcarrieranddetectorgasesiscriticalforoptimumand
the sulfur chemiluminescent detector but other sulfur specific
consistent analytical performance. Control is achieved by use
detectors can be used provided they have sufficient sensitivity,
of pressure regulators and fixed flow restrictors. The gas flow
respond to all eluted sulfur compounds, do not suffer from
is measured by appropriate means and adjusted. Mass flow
interferences and satisfy quality assurance criteria. Regulatory
controllers, capable of maintaining gas flow constant to 61%
agencies may require demonstration of equivalency of alterna-
at the flow rates necessary for optimal instrument performance
tive detection systems to the SCD.
can be used.
5.1.3 Detector—Sulfur compounds are processed using a
4. Significance and Use
flameionizationdetector(FID),aheatedcombustionzoneora
4.1 Many sources of natural and petroleum gases contain
similar device. The products are collected and delivered to a
sulfurcompoundsthatareodorous,corrosive,andpoisonousto
sulfur chemiluminescence detector (SCD).
catalysts used in gaseous fuel processing.
5.1.3.1 FID—The detector must meet or exceed the speci-
4.2 Low ppm amounts of sulfur odorants are added to
fications in Table 1 of Practice E594 while operating within
natural gas and LP gases for safety purposes. Some odorants
manufacturers specifications. The detector must be capable of
are unstable and react to form compounds having lower odor
operating at the maximum column temperature. The flow path
thresholds. Quantitative analysis of these odorized gases en-
from the injection system through the column to the FID must
sures that odorant injection equipment is performing to speci-
remain at or above the column temperature throughout the
fication.
analysis. The FID must allow for the insertion of a SCD
4.3 Although not intended for application to gases other
sampling probe into the flame without compromising the
than natural gas and related fuels, this test method has been
abilityoftheFIDtodetecthydrocarbons.Flowratesofairand
successfully applied to fuel type gases including refinery,
hydrogen or, alternatively of oxygen and hydrogen, must be
landfill, cogeneration, and sewage digester gas. Refinery,
optimized to produce a hydrogen rich flame or combustion
landfill, sewage digester and other related fuel type gases
zone that is capable of combusting hydrocarbons. This is
inherentlycontainvolatilesulfurcompoundsthataresubjectto
necessary to minimize matrix effects. When performing the
federal, state, or local control. The methane fraction of these
simultaneous detection of hydrocarbons is necessary, a FID
fuel type gases are occasionally sold to distributors of natural
and heated combustion zone can be used in series. Zero air is
gas.Forthesereasons,bothregulatoryagenciesandproduction
necessary when performing the simultaneous determination of
and distribution facilities may require the accurate determina-
sulfur gases and hydrocarbons.
tion of sulfur to satisfy regulatory, production or distribution
5.1.3.2 SCD—The sulfur chemiluminescence detector shall
requirements. Fuel gases are also used in energy production or
meet or exceed the following specifications: (1) greater than
areconvertedtonewproductsusingcatalyststhatarepoisoned
10 linearity, (2) less than 5 pg S/s sensitivity, (3) greater than
byexcessivesulfurinthefeedgas.Industryfrequentlyrequires
10 selectivityforsulfurcompoundsoverhydrocarbons,(4)no
measurement of sulfur in these fuel type gases to protect their
quenching of sulfur compound response, and (5) no interfer-
catalyst investments.
ence from co-eluting compounds at the usual GC sampling
4.4 Analytical Methods—Gas chromatography (GC) is
volumes.
commonly used in the determination of fixed gas and organic
5.1.3.3 Heated Combustion Zone—Sulfur compounds elut-
composition of natural gas (Test Method D1945). Other
ingfromthechromatographiccolumnareprocessedinaheated
standardASTMmethodsfortheanalysisofsulfurinfuelgases
hydrogen rich combustion zone or a flame ionization detector
include Test Methods D1072 and D4468 for total sulfur and
fitted to the end of the column. Products are transferred under
Test Methods D4010 and D4884 for hydrogen sulfide.
reduced pressure to the reaction chamber of a chemilumines-
5. Apparatus
cence detector. An excess of ozone present in the chamber
reacts with the sulfur combustion product(s) to liberate blue
5.1 Chromatograph—Any gas chromatograph of standard
(480 nm) and ultraviolet light (260 nm).
manufacture, with hardware necessary for interfacing to a
chemiluminescence detector and containing all features neces- 5.1.3.4 SCD operation is based on the chemiluminescence
sary for the intended application(s) can be used. Chromato- (light emission) produced by the reaction of ozone with an
graphicparametersmustbecapableofobtainingretentiontime unidentified sulfur species produced in a combustion zone,
repeatability of 0.05 min (3 s) throughout the scope of this flame ionization detector or related device.The chemilumines-
analysis. cent sulfur species is the subject of on-going research. The
5.1.1 Sample Inlet System—A sample inlet system capable appendix describes two chemiluminescence reaction models.
ofoperatingcontinuouslyatthemaximumcolumntemperature The sulfur combustion product(s) and an excess of ozone are
is used. A split/splitless injection system capable of splitless drawn into a low pressure (<20 Torr) reaction cell. The ozone
operation and split control from 10:1 up to 50:1 may be used reacts to produce blue light (480 nm), oxygen, and other
with capillary columns, or when interferants are encountered. products. A blue sensitive photomultiplier tube detects the
An automated gas sampling valve is required for many emitted light which is then amplified for display or output to a
applications. The inlet system must be conditioned or con- data collection system.
D5504–01 (2006)
TABLE 2 Typical Gas Chromatographic Operating Parameters
5.2 Column—A variety of columns can be used in the
determination of sulfur compounds. Typically, a 60 m 3 0.54 Injector, gas sample loop: 150°C 0.5 cc
Injector, splitless: 150°C 100 % sample to
mmIDfusedsilicaopentubularcolumncontaininga5µmfilm
column
thickness of bonded methyl silicone liquid phase is used. The
Flame ionization detector (FID): 250°C
selected column must provide retention and resolution charac- H2: 200 cm /min
Air: 400 cm /min
teristics such as listed in Table 2 and illustrated in Fig. 1. The
Make-up gas (He): 20 cm /min
column must be inert towards sulfur compounds. The column
Or a Heated combustion zone 800°C
(HCZ):
must also demonstrate a sufficiently low liquid phase bleed at
H2: 100 cm /min
high temperature such that loss of the SCD response is not
Air: 40 cm /min
encountered while operating the column at 200°C.
SCD: output at 0–1 V cell pressure at 6.0 torr
Column Program: 1.5 min at 30°C
5.3 Data Acquisition:
15.0°/min to 200°C
5.3.1 Recorder—A 0 to 1 mV range recording potentiom-
hold at 200°C as required
eter or equivalent, with a full-scale response time of2sor less
Carrier gas (helium): adjust to methane retention time of 1.10 min
Carrier: 11 cm /min
can be used.
5.3.2 Integrator—An electronic integrating device or com-
puter can be used. A dual channel system is necessary for
simultaneousacquisitionofboththeFIDandSCDsignals.The
device and software must have the following capabilities:
5.3.2.1 Graphic presentation of the chromatogram.
5.3.2.2 Digital display of chromatographic peak areas.
5.3.2.3 Identification of peaks by retention time or relative
retention time, or both.
TABLE 1 Example Retention Times Using 4µ Capillary Column
(30 m 3 0.32 mm)
Conditions as in Table 2
Compound Ave. RT min Compound Ave. RT min
Methane 1.458 ?S 16.363
Ethane 1.730 n-Octane 16.423
Ethylene 1.733 ?S 16.425 FIG. 1 Standard: Perm Tube Analysis Run
Hydrogen Sulfide 2.053 ?S 16.592
Propylene 2.550 ?S 16.692
Carbonyl Sulfide 2.586 ?-EtThiophene 16.983
5.3.2.4 Calculation and use of response factors.
Propane 2.679 ?S 17.183
5.3.2.5 External standard calculation and data presentation.
Sulfur Dioxide 2.815 ?S 17.319
i-Butane 4.422 ?S 17.631
6. Reagents and Materials
Butene-1 5.263 ?S 17.754
n-Butane 5.578q m&p-Xylene 17.788
NOTE 1—Warning:Sulfur compounds contained in permeation tubes
Methanethiol 5.804 ?S 17.913
or compressed gas cylinders may be flammable and harmful or fatal if
t-Butene-2 5.938 ?S 18.063
ingested or inhaled. Permeation tubes and compressed gas standards
2,2-DMO3 6.009 ?S 18.139
c-Butene-2 6.409 o-Xylene 18.279
should only be handled in well ventilated locations away from sparks and
3-Me-Butene-1 7.463 n-None 18.448
flames. Improper handling of compressed gas cylinders containing air,
i-Pentane 8.035 ?S 18.450
nitrogen or helium can result in explosion. Rapid release of nitrogen or
Pentene-1 8.500 ?S 18.567
helium can result in asphyxiation. Compressed air supports combustion.
Ethanethiol 8.583 ?S 18.642
2-Me-Butene-1 8.717 DiEthylDiSulfide 18.767
6.1 Sulfur Standards—Accurate sulfur standards are re-
n-Pentane 8.860 ?S 18.911
quired for sulfur gas quantitation. Permeation and compressed
Isoprene 8.983 ?S 19.008
gas standards should be stable, of high purity, and of the
t-Pentene-2 9.096 ?S 19.125
Dimethylsulfide 9.117 ?S 19.292
highest available accuracy.
o-Pentene-2 9.321 ?S 19.979
6.1.1 Permeation Devices—Sulfur standards can consist of
2-Me-Butene-2 9.463 2,2,4-TriMeBz 20.227
permeation tubes, one for each selected sulfur species gravi-
Carbon Disulfide 9.617 n-Decane 20.308
2,2-DMO4 9.898 ?S 20.550
metrically calibrated and certified at a convenient operating
i-Propanethiol 10.222 ?S 21.396
temperature.With constant temperature, calibration gases cov-
Cyclopentene 10.392 ?S 21.733
3-MePentadiene 10.525 ?S 21.808 ering a w
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.