ASTM D7041-04(2010)
(Test Method)Standard Test Method for Determination of Total Sulfur in Light Hydrocarbons, Motor Fuels, and Oils by Online Gas Chromatography with Flame Photometric Detection
Standard Test Method for Determination of Total Sulfur in Light Hydrocarbons, Motor Fuels, and Oils by Online Gas Chromatography with Flame Photometric Detection
SIGNIFICANCE AND USE
This test method can be used to determine total sulfur levels in process feeds and finished products that fall within the scope of this test method.
Low levels of sulfur in process feed stocks can poison expensive catalysts used in petroleum refining processes. This test method can be used to monitor sulfur levels in these feedstocks.
SCOPE
1.1 This test method covers the determination of total sulfur in liquid hydrocarbons with a final boiling point less than 450°C by gas chromatography using a flame photometric detector.
1.2 This test method is applicable for total sulfur levels from 0.5 to 100 mg S/kg.
Note 1—The pooled limit of quantification (PLOQ) derived from the 2002 interlaboratory cooperative test program was determined to be 1 mgS/kg.
Note 2—Samples can also be tested at other total sulfur levels, but the precision statements may not apply.
1.3 The values stated in SI units are to be regarded as standard.
1.4 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 specific hazard statements see Section 7.
General Information
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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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: D7041 − 04(Reapproved 2010)
Standard Test Method for
Determination of Total Sulfur in Light Hydrocarbons, Motor
Fuels, and Oils by Online Gas Chromatography with Flame
Photometric Detection
This standard is issued under the fixed designation D7041; 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 E840 PracticeforUsingFlamePhotometricDetectorsinGas
Chromatography
1.1 This test method covers the determination of total sulfur
in liquid hydrocarbons with a final boiling point less than
3. Summary of Test Method
450°C by gas chromatography using a flame photometric
3.1 The sample is analyzed by gas chromatography with a
detector.
flame photometric detector. A fixed amount of sample is
1.2 Thistestmethodisapplicablefortotalsulfurlevelsfrom
injected into the gas chromatograph where it is vaporized. The
0.5 to 100 mg S/kg.
air carrier stream carries the vaporized sample into a high
NOTE 1—The pooled limit of quantification (PLOQ) derived from the
temperature zone (>900°C) where the compounds present in
2002 interlaboratory cooperative test program was determined to be 1
the sample are oxidized. Sulfur compounds are converted to
mgS/kg.
sulfur dioxide (SO ). The carrier stream carries the oxidation
NOTE 2—Samples can also be tested at other total sulfur levels, but the
precision statements may not apply.
components onto a chromatographic column where they are
separated and the SO is quantified by the flame photometric
1.3 The values stated in SI units are to be regarded as
detector.Calibrationofthedetectorisachievedbytheuseofan
standard.
appropriate external standard.
1.4 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
4. Significance and Use
responsibility of the user of this standard to establish appro-
4.1 This test method can be used to determine total sulfur
priate safety and health practices and determine the applica-
levelsinprocessfeedsandfinishedproductsthatfallwithinthe
bility of regulatory limitations prior to use. For specific hazard
scope of this test method.
statements see Section 7.
4.2 Low levels of sulfur in process feed stocks can poison
2. Referenced Documents
expensive catalysts used in petroleum refining processes. This
2.1 ASTM Standards:
test method can be used to monitor sulfur levels in these
D1298 Test Method for Density, Relative Density (Specific
feedstocks.
Gravity), or API Gravity of Crude Petroleum and Liquid
5. Apparatus
Petroleum Products by Hydrometer Method
D4052 Test Method for Density, Relative Density, and API
5.1 Gas Chromatograph, equipped with automatically con-
Gravity of Liquids by Digital Density Meter
trolled valves, capable of automatic calibration with an exter-
D4057 Practice for Manual Sampling of Petroleum and
nal standard and having a flame photometric detector with an
Petroleum Products
overall sensitivity to detect at least 0.5 mg/kg of SO . It must
D4177 Practice for Automatic Sampling of Petroleum and
be able to automatically control all valve switching times.
Petroleum Products
Although originally developed with online analytical measure-
mentequipmentinanofflinemodeofoperation,suitableonline
This test method is under the jurisdiction of ASTM Committee D02 on
or laboratory gas chromatographs may apply this test method
Petroleum Products and Lubricantsand is the direct responsibility of Subcommittee
as described. Typical instrument parameters are listed in Table
D02.03 on Elemental Analysis.
1.
Current edition approved May 1, 2010. Published May 2010. Originally
5.1.1 Carrier and Detector Gas Control—The chromato-
approved in 2004. Last previous edition approved in 2004 as D7041–04. DOI:
10.1520/D7041-04R10.
graph must be equipped with flow controllers or pressure
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
controllers capable of maintaining a constant supply of carrier
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
gas and detector supply gases. Electronic pressure or flow
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. control is highly recommended.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7041 − 04 (2010)
TABLE 1 Typical Instrument Parameters
where such specifications are available. Other grades may be
Carrier gas Zero air used, provided it is first ascertained that the reagent is of
Carrier flow rate 30 mL/min
sufficiently high purity to permit its use without lessening the
Hydrogen flow rate 60 mL/min
accuracy of the determination.
Detector Flame photometric detector
Detector temperature 120°C
6.2 Carrier-Gas—Zero grade air is recommended.
Injector temperature 285°C
(Warning—Compressed air is a gas under high pressure that
Furnace temperature 1000°C
Column 40 ft by ⁄8 in. stainless steel
supports combustion.)
tubing,
12 % polyphenyl ether/1.5 % 6.3 Hydrogen—Chromatographic grade recommended,
H PO
3 4
minimum purity 99.995 %. (Warning— Hydrogen is an ex-
on 40/60 Chromosorb T
tremely flammable gas under high pressure.)
Column temperature 115°C
6.4 Solvent (Reagent Grade)—the solvent chosen should be
capable of dissolving the sulfur-containing compound used to
prepare the standard. The solvent of choice should have a
density similar to the samples being analyzed and it should
5.1.2 Sample Injection System—An automatic sample injec-
have sulfur concentrations less than the instrument detection
tion device is required. The injector must allow the introduc-
limit. Mixed solvents such as an isooctane / toluene mixture
tion of small sample sizes (0.1 to 1 µL). The sample must be
can be used to reach the desired density. (Warning— Solvents
accurately and repeatably injected into the gas chromatograph.
used as reagents such as toluene and iso octane are flammable
Rotary or stem type liquid injection valves or auto injectors are
and may be harmful or fatal if ingested or inhaled.)
recommended. The valve or injector must be equipped with a
6.5 Standards for Calibration and Peak Identification—
heated vaporizer section capable of being heated to at least
Standards are used for peak identification and retention time
285°C.
determination. Also standards of known concentrations are
5.2 Pyrolysis Furnace—Afurnace capable of maintaining a required for external standard calibration of the gas chromato-
sufficient temperature (>900°C) to pyrolyze the entire sample graph.
and oxidize the sulfur compounds to SO . 6.5.1 Preparation of Stock Solution (mass/volume), 100 µg
S/mL (see Notes 3 and 4).Accurately weigh to the nearest 0.1
5.3 Quartz Combustion Tube—Quartz tube capable of with-
mg, 0.0456 g of butyl sulfide into a suitable container such as
standing temperatures up to 1200°C. The oxidation section
a 100 mL volumetric flask. Dilute to volume with the selected
shall be large enough to ensure complete oxidation of the
solvent.Thisstocksolutioncanbefurtherdilutedtothedesired
sample.
sulfur concentration. Other sulfur containing compounds such
5.4 Column—A column that can provide complete separa-
as thiophene or thianaphthene can be substituted for n-butyl
tion of SO from the CO quench and the other oxidized sulfide if desired. The concentration of the stock solution can
2 2
components such as H O. be calculated as follows:
µg S/mL 5 ~M 332.06! 3 ~1 310 !~µg/g!/~100 mL 3 FW! (1)
5.5 Detector—Any flame photometric detector (FPD) can
be used, provided it can detect a minimum peak height twice
where:
that of the baseline noise fora1µL injection of a 0.5 mg S/kg
M = exact mass of sulfur reference compound (g), and
standard. Detector linearity shall be at least equal to or greater
FW = formula weight of sulfur reference compound.
than 10 .The user is referred to Practice E840 for assistance in
NOTE 3—Commercial standards can be used provided they are checked
optimizing the operation and performance of the FPD.
for accuracy.
NOTE 4—Stock solutions will have a shelf life of approximately 2 to 3
5.6 Data Acquisition System—Use any integrator or com-
months and should be remixed accordingly.
puterized data acquisition system for peak area integration, as
6.5.2 Preparation of Stock Solution: (mass/mass), 100 µg
well as for recording the chromatographic trace. The device
S/g (see Notes 3 and 4). Accurately weigh to the nearest 0.1
and software must have the following capabilities:
mg, 0.0456 g of butyl sulfide into a suitable container.Add 100
5.6.1 Identification of peak by retention time.
g (accurately weighed to the nearest 0.1 g) of the selected
5.6.2 Calculation and use of response factors.
solvent.Thisstocksolutioncanbefurtherdilutedtothedesired
5.6.3 External standard calibration calculation.
sulfur concentration. Other sulfur containing compounds such
5.6.4 Graphic presentation of the chromatogram.
as thiophene or thianaphthene can be substituted for butyl
sulfide if desired. The concentration of the stock solution can
5.7 Analytical Balance—Any balance capable of accurately
be
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