Standard Test Method for Total Sulfur in Aromatic Compounds by Hydrogenolysis and Rateometric Colorimetry (Withdrawn 2008)

SIGNIFICANCE AND USE
Sulfur can be a catalyst poison in the aromatic chemical manufacturing process. This test method can be used to monitor the amount of sulfur in aromatic hydrocarbons. This test method may also be used as a quality control tool and in setting specifications for sulfur determination in finished products.
SCOPE
1.1 This test method covers the determination of sulfur in aromatic hydrocarbons, their derivatives, and related chemicals having typical sulfur concentrations from 0.020 to to 10mg/kg.
WITHDRAWN RATIONALE
This test method covers the determination of sulfur in aromatic hydrocarbons, their derivatives, and related chemicals having typical sulfur concentrations from 0.020 to 10 mg/kg.
Formerly under the jurisdiction of Committee D16 on Aromatic Hydrocarbons and Related Chemicals, this test method was withdrawn in August 2008 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.

General Information

Status
Withdrawn
Publication Date
09-Jan-1999
Withdrawal Date
23-Sep-2008
Current Stage
Ref Project

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ASTM D6212-99 - Standard Test Method for Total Sulfur in Aromatic Compounds by Hydrogenolysis and Rateometric Colorimetry (Withdrawn 2008)
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D6212–99
Standard Test Method for
Total Sulfur in Aromatic Compounds by Hydrogenolysis and
Rateometric Colorimetry
This standard is issued under the fixed designation D 6212; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 4790 Terminology of Aromatic Hydrocarbons and Re-
lated Chemicals
1.1 This test method covers the determination of sulfur in
E29 Practice for Using Significant Digits in Test Digits in
aromatichydrocarbons,theirderivatives,andrelatedchemicals
Test Data to Determine Conformance with Specifications
having typical sulfur concentrations from 0.020 to 10 mg/kg.
2.2 Other Documents:
1.2 This test method may be extended to higher concentra-
OSHA Regulations, 29 CFR paragraphs 1910.1 and
tions by dilution.
1910.1200
1.3 This test method is applicable to aromatic hydrocarbons
and related chemicals such as benzene, toluene, cumene,
3. Terminology
p-xylene, o-xylene, and to cyclohexane.
3.1 See Terminology D 4790 for definition of terms used in
1.4 The following applies to all specified limits in this test
this test method.
method: for purposes of determining conformance with this
standard, an observed value or a calculated value shall be
4. Summary of Test Method
rounded off to the nearest unit in the last right-hand digit used
4.1 Reductive Configuration—The sample is injected at a
for expressing the specification limit in accordance with the
constant rate into a hydrogenolysis apparatus. Within this
rounding-off method of PracticeE29.
apparatus the sample is pyrolyzed at temperatures in the range
1.5 This standard does not purport to address all the safety
of 1200°C to 1300°C and in the presence of excess hydrogen.
concerns, if any, associated with its use. It is the responsibility
Sulfur compounds are reduced to hydrogen sulfide (H S).
of the user of this standard to establish appropriate safety and
Analysis is by rateometric detection of the colorimetric reac-
health practices and determine the applicability of regulatory
tion of H S with lead acetate. Hydrocarbon components are
limitations prior to use.Specific precautionary statements are
converted to gaseous such as methane during hydrogenolysis.
given in 6.4, 7.5, 7.7, and 8.1.
4.2 OxyhydroPyrolysis Configuration—Sample is injected
at a constant rate into an air stream and introduced into a
2. Referenced Documents
pyrolysis furnace. The sample flows through an inner tube
2.1 ASTM Standards:
2 within the furnace where it combusts with the oxygen in the air
D 1193 Specification for Reagent Water
carrier. SO and SO are formed from the sulfur compounds in
2 3
D 3437 Practice for Sampling and Handling Liquid Cyclic
3 the sample. The sample then leaves the inner tube within the
Products
pyrolyzer and is mixed with hydrogen within the main reaction
D 4045 Test Method for Sulfur in Petroleum Products by
4 tube and is pyrolyzed at temperatures in the range of 1200°C
Hydrogenolysis and Rateometric Colorimetry
to 1300°C (see Fig. 1). The SO and SO formed within the
2 3
D 4052 Test Method for Density and Relative Density of
4 inner tube are then reduced to H S. Analysis is by rateometric
Liquids by Digital Density Meter
detection of the colorimetric reaction of H S with lead acetate.
5. Significance and Use
This test method is under the jurisdiction of ASTM Committee D16 on
5.1 Sulfur can be a catalyst poison in the aromatic chemical
Aromatic Hydrocarbons and Related Chemicals and is the direct responsibility of
manufacturing process. This test method can be used to
Subcommittee D16.04 on Instrumental Analysis.
Current edition approved Jan. 10, 1999. Published March 1999. Originally
published as D 6212 – 97. Last previous edition D 6212 – 97.
2 5
Annual Book of ASTM Standards, Vol 11.01. Annual Book of ASTM Standards, Vol 14.02.
3 6
Annual Book of ASTM Standards, Vol 06.04. Available from Superintendent of Documents, U.S. Government Printing
Annual Book of ASTM Standards, Vol 05.02. Office, Washington, DC 20402.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6212–99
FIG. 1 Oxyhydrogen Furnace Adapter

D6212–99
monitor the amount of sulfur in aromatic hydrocarbons. This 6.6 Recorder—Achart recorder with 10-V full scale and 10
test method may also be used as a quality control tool and in kVinputimpedanceorgreaterisrequired,havingachartspeed
setting specifications for sulfur determination in finished prod- of 0.5 to 3 cm/min. An attenuator may be used for more
ucts. sensitive recorders.
6.7 Pyrometer—A pyrometer with a 25-cm long thermo-
couple suitable for use at 500 to 1400°C. Diameter must be
6. Apparatus
small enough to fit through the injection tube of the oxyhydro-
6.1 The apparatus of this test method can be setup in two
gen furnace adapter.Type K with a 316 stainless steel sheath is
different configurations, which will be described herein as the
suitable.
“reductive pyrolysis” configuration, and the “oxyhydropyroly-
sis” configuration. The reductive pyrolsis configuration is the
7. Reagents and Materials
one referenced inTest Method D 4045.The oxyhydropyrolysis
7.1 Purity of Chemicals—Reagent grade chemicals shall be
configuration is a modification of the reductive pyrolysis
used in all tests. Unless otherwise indicated, it is intended that
configuration that minimizes the formation of coke within the
all reagents shall conform to the specifications of the Commit-
pyrolysis furnace when running aromatic samples. Both setups
tee onAnalytical Reagents of theAmerican Chemical Society,
can be used to measure sulfur in aromatic compounds as
where such specifications are available. Other grades may be
outlined in this test method.
used, provided it is first ascertained that the reagent is of
6.2 Pryolysis Furnace—A tube furnace that can provide an
sufficiently high purity to permit its use without lessening the
adjustable temperature of 900 to 1400°C. An 8-mm or larger
accuracy of the determination.
inner diameter is required in the furnace to fit reaction tubes of
7.2 Purity of Water—Unless otherwise indicated, reference
sufficient size to pyrolyze the sample.
to water shall be understood to mean Type IV, reagent grade
water, conforming to Specification D 1193.
6.2.1 Oxyhydrogen Furnace Adapter—An apparatus, used
7.3 Sensing Tape—Lead-acetate-impregnated analytical-
in the oxyhydropyrolysis set up, that fits to the front of the
quality filter paper shall be used.
reaction tube and adds an injection tube that extends partially
7.4 Acetic Acid (5 %)—Mix 1 part by volume reagent grade
within the main reaction tube to about 1/2 way into the furnace
glacial acetic acid with 19 parts water to prepare 5 % acetic
(see Fig. 1). The oxidative process occurs in the injection tube,
acid solution.
then the combustion products of the sample are injected into
7.5 Hydrogen Gas—Use sulfur-free hydrogen of laboratory
the flow of hydrogen at the hot zone.
grade.
6.2.2 Water Removal Apparatus—A device that attaches
NOTE 2—Warning: Hydrogen has wide explosive limits when mixed
close to the outlet of the pyrolysis furnace, used in the
with air.
oxyhydropyrolysis set up to remove excess moisture from the
sample stream. Both membrane counter flow driers or coalesc-
7.6 Purge Gas—Sulfur-free purge gas, nitrogen, CO,or
ing filters held at sub-ambient temperatures have been found to other inert gas. Commercial grade cylinder gas is satisfactory.
be suitable. 7.7 Instrument Air—Use dry, sulfur-free air. Nitrogen/
oxygen, or helium/oxygen bottled gas blends containing no
6.3 Rateometric H S Detector—Hydrogenolysis products
more than 30 % oxygen by volume can be used where air
contain H S in proportion to sulfur in the sample. The HSis
2 2
utilities are not available.
measured by measuring rate of change of reflectance caused by
darkening when lead sulfide is formed. Rateometric electron-
NOTE 3—Warning: Do not use pure oxygen as a substitute for instru-
ics, adapted to provide a first derivative output, allows suffi- ment air.
cient sensitivity to measure below 0.01 mg/L.
7.8 Toluene, (sulfur free).
6.4 Hypodermic Syringe—A hypodermic having a needle
7.9 Thiophene, 99+ % purity.
long enough to reach into the pyrolyzer reaction tube to the
550°C zone is required. Usually a 75-mm long needle is
8. Hazards
sufficientforthestraightreductivesetup.Theoxyhydropyrolsis
8.1 Consult current OSHA regulations, suppliers Material
setup requires a needle length of 150 mm. A side port is
Safety Date Sheets, and local regulations for all materials used
convenient for vacuum filling and for flushing the syringe. A
in this test method.
100-µLsyringe is satisfactory for injection rates down to 3 µL/
min. and a 25-µL syringe for lower rates.
9. Sampling
9.1 Use the practices in accordance with Practice D 3437.
NOTE 1—Warning: Exercise caution as hypodermics can cause acci-
dental injury.
6.5 Syringe Injection Drive—The drive must provide uni-
form, continuous sample injections.Variation in drive injection
Reagent Chemicals, American Chemical Society Specifications,American
Chemical Society, Washing ton, DC. For suggestions on the testing of reagents not
rate caused by mechanical irregularities of gears will cause
listed by the American Chemical Society, see Analar Standards for Laboratory
noise in the reading of the detector. The adjustable drive must
Chemicals,BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeial
be capable of injection rates from 6 µL/min. to 0.06 µL/min.
and National Formulary,U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,
over a 6-min interval. MD.
D6212–99
10. Calibration Standards volume acetic acid solution. Set pyrolysis furnace temperature
to 1200°C and allow system to come to temperature. Purge
10.1 Prepare a reference standard solution or solutions of
system with inert gas and check all conne
...

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