ASTM D4208-02(2007)
(Test Method)Standard Test Method for Total Chlorine in Coal by the Oxygen Bomb Combustion/Ion Selective Electrode Method
Standard Test Method for Total Chlorine in Coal by the Oxygen Bomb Combustion/Ion Selective Electrode Method
SIGNIFICANCE AND USE
The purpose of this test method is to measure the total chlorine content of coal. The chlorine content of coals may be useful in the evaluation of slagging problems, corrosion in engineering processes, and in the total analysis of coal and coke. When coal samples are combusted in accordance with this method, the chlorine is quantitatively retained and is representative of the total chlorine content of the whole coal.
SCOPE
1.1 This test method covers the analysis of total chlorine in coal.
1.2 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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: D4208 − 02(Reapproved 2007)
Standard Test Method for
Total Chlorine in Coal by the Oxygen Bomb Combustion/Ion
Selective Electrode Method
This standard is issued under the fixed designation D4208; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope coke. When coal samples are combusted in accordance with
this method, the chlorine is quantitatively retained and is
1.1 This test method covers the analysis of total chlorine in
representative of the total chlorine content of the whole coal.
coal.
1.2 This standard does not purport to address all of the
5. Apparatus
safety concerns, if any, associated with its use. It is the
5.1 Combustion Bomb, constructed of materials that are not
responsibility of the user of this standard to establish appro-
affected by the combustion process or products. The bomb
priate safety and health practices and determine the applica-
mustbedesignedsothatallliquidcombustionproductscanbe
bility of regulatory limitations prior to use.
quantitatively recovered by washing the inner surfaces. There
2. Referenced Documents must be no gas leakage during the test. The bomb must be
capableofwithstandingahydrostatic-pressuretestto3000psig
2.1 ASTM Standards:
(approximately20MPa)atroomtemperaturewithoutstressing
D1193Specification for Reagent Water
any part beyond its elastic limit.
D3173Test Method for Moisture in theAnalysis Sample of
Coal and Coke 5.2 Water Bath—A container large enough to hold the
D3180Practice for Calculating Coal and Coke Analyses combustion bomb and enough cooling water to dissipate the
from As-Determined to Different Bases heat generated during the combustion process. The container
E144Practice for Safe Use of Oxygen Combustion Bombs shall be designed to allow a constant flow of water around the
E691Practice for Conducting an Interlaboratory Study to combustion bomb.
Determine the Precision of a Test Method
5.3 Combustion Crucibles—Samples shall be burned in an
open crucible of platinum, quartz, or acceptable base-metal
3. Summary of Test Method
alloy.
3.1 Total chlorine is determined in this method by combus-
5.4 Firing Wire, 100-mm, nickel-chromium alloy, No. 34B
ting a weighed sample in an oxygen bomb with dilute base
& S gage, or platinum, No. 34 or No. 38B & S gage.
adsorbingthechlorinevapors.Thebombisrinsedintoabeaker
with water and following the addition of an ionic strength
5.5 Firing Circuit—A6to16-Valternatingordirectcurrent
adjuster, the chloride is determined by ion-selective electrode. is required for ignition purposes with an ammeter or pilot light
in the circuit to indicate when current is flowing.Astep-down
4. Significance and Use
transformer connected to an alternating-current lighting circuit
or batteries can be used. (Warning—The ignition circuit
4.1 The purpose of this test method is to measure the total
switch shall be of the momentary double-contact type, nor-
chlorine content of coal. The chlorine content of coals may be
mally open, except when held closed by the operator. The
useful in the evaluation of slagging problems, corrosion in
switch should be depressed only long enough to fire the
engineering processes, and in the total analysis of coal and
charge.)
5.6 Balance, analytical, with a sensitivity of 0.1 mg.
This test method is under the jurisdiction of ASTM Committee D05 on Coal
and Coke and is the direct responsibility of Subcommittee D05.21 on Methods of
5.7 Specific-Ion Meter—A pH meter with an expandable
Analysis.
millivolt scale, specific-ion meter, sensitive to 0.1 mV, suitable
Current edition approved May 1, 2007. Published May 2007. Originally
ϵ1 for method of standard addition determinations.
approved in 1982. Last previous edition approved in 2002 as D4208–88 (2002)
. DOI: 10.1520/D4208-02R07.
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
Standards volume information, refer to the standard’s Document Summary page on Midgley, D., and Torrance, K., Potentiometric Water Analysis, John Wiley and
the ASTM website. Sons, 1978.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4208 − 02 (2007)
5.8 Electrodes, chloride-sensing, with the appropriate 8.3 Assemble the bomb in the normal manner and charge it
reference-typeelectrodeasrecommendedbythemanufacturer. withoxygentoapressurebetween20and30atm(2to3MPa).
If the oxygen should exceed the specified pressure, do not
6. Reagents
proceed with the combustion. In this case, detach the filling
connection, exhaust the bomb in the usual manner, and discard
6.1 Purity of Reagents—Reagent grade chemicals shall be
the sample. (Warning—The following precautions are recom-
used in all tests. Unless otherwise indicated, it is intended that
mended for safe operations in the use of the oxygen combus-
all reagents shall conform to the specifications of the Commit-
tion bomb.Additional precautions are given in Recommended
tee onAnalytical Reagents of theAmerican Chemical Society,
Practice E144, for use of oxygen combustion bombs.)
where such specifications are available. Other grades may be
8.3.1 The weight of coal sample and the pressure of the
used, provided it is first ascertained that the reagent is of
oxygen admitted to the bomb must not exceed the bomb
sufficiently high purity to permit its use without lessening the
manufacturer’s recommendation.
accuracy of the determination.
8.3.2 Inspect the bomb parts carefully after each use.
6.2 Purity of Water, deionized, high-purity, low-specific
Frequently check the threads on the main closure for wear.
conductivity, Type II reagent water as defined in Specification
Replace the cracked or significantly worn parts. Return the
D1193.
bomb to the manufacturer occasionally for inspection and
6.3 Ionic Strength Adjuster Solution (5M NaNO )—
3 possibly proof testing.
Dissolve 42.5 g of sodium nitrate in 100 mL water.
8.3.3 The oxygen supply cylinder should be equipped with
an approved type of safety device, such as a reducing valve, in
6.4 Sodium Carbonate Solution(Na CO)(2%)—Dissolve
2 3
addition to the needle valve and pressure gage used in
2.0 g of sodium carbonate in 100 mL water.
regulating the oxygen feed to the bomb. Valves, gages, and
6.5 Chloride, Standard Stock Solution (1000 µg/mL)—
gaskets must meet industry safety code. Suitable reducing
Dissolve 1.6486 g of sodium chloride (NaCl) in water and
valves and adaptors for 300 to 500-psi (approximately 3 to
dilute to 1 L. The NaCl should be dried for1hat 105°C and
5-MPa) discharge pressure are obtainable from commercial
cooled to room temperature in a desiccator before weighing.
sources of compressed-gas equipment. Check the pressure
6.6 Chloride, Standard Stock Solution (100 µg/mL)—Dilute
gage periodically for accuracy.
10.0 mL of chloride stock solution to 100 mL in a volumetric
8.3.4 During ignition of a sample, the operator must not
flask with water.
permit any portion of his body to extend over the combustion
bomb or its container.
6.7 Oxygen,freeofcombustiblematterandguaranteedtobe
8.3.5 Exercise extreme caution when combustion aids are
99.99% pure.
employed so as not to exceed the bomb manufacturer’s
recommendations and to avoid damage to the bomb.
7. Sample
8.3.6 Admit oxygen slowly into the bomb to avoid blowing
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.