ASTM D4755-95(2010)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D4755 − 95(Reapproved 2010)
Standard Test Method for
Free Halogens in Halogenated Organic Solvents and Their
Admixtures
This standard is issued under the fixed designation D4755; 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 5. Interferences
5.1 The following materials interfere with this test giving a
1.1 This test method covers the evaluation of free halogens
false positive: ferric ion; phosgene; iodine; oxidizing agents;
in halogenated organic solvents and their admixtures.
and strong acid (catalyze atmospheric oxidation of the KI).
1.2 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
6. Apparatus
responsibility of the user of this standard to establish appro-
6.1 Glass-Stoppered Graduate, 25-mL.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
7. Reagents
7.1 Purity of Reagents—Reagent grade chemicals shall be
2. Referenced Documents
used in all tests. Unless otherwise indicated, it is intended that
2.1 ASTM Standards:
all reagents shall conform to the specifications of the Commit-
D1193 Specification for Reagent Water
tee onAnalytical Reagents of theAmerican Chemical Society,
where such specifications are available. Other grades may be
3. Summary of Test Method
used, provided it is first ascertained that the reagent is of
sufficiently high purity to permit its use without lessening the
3.1 Anyfreehalogenspresentinthehalogenatedsolventare
accuracy of the determination.
extracted with water and reacted with potassium iodide test
7.2 Purity of Water—Unlessotherwiseindicated,references
solution containing starch indicator.Ablue color indicates that
to water shall be understood to mean reagent water conforming
presence of free halogens.
to Type III of Specification D1193.
4. Significance and Use
7.3 Potassium Iodide (KI) Test Solution—Dissolve 16.5 g of
potassium iodide in water to make 100 mL. Store in light-
4.1 Free halogens will react with any residual moisture in a
resistant containers.
solvent to form acid. These acids can cause corrosion to
process and storage equipment used for halogenated solvents.
7.4 Starch Test Solution—Mix1gof soluble starch with 10
mg of red mercuric iodide and sufficient cold water to make a
4.2 The presence of free halogens in halogenated solvents is
thin paste. Add 200 mL of boiling water, and boil for 1 min
often an indication that the stabilizers in the solvent system are
with continuous stirring. Cool, and use only the clear solution.
breaking down.
8. Procedure
4.3 This test method provides a means of detecting the
presence of free halogens in halogenated solvents and their
8.1 Transfer 10 mL of sample to a glass-stoppered graduate
admixtures.
and add 10 mL of potassium iodide test solution and 1 mL of
starch indicator solution. Shake vigorously for 2 min and
observe color of the aqueous layer. The presence of free
1 halogens is indicated by a blue coloration.
This test method is under the jurisdiction of ASTM Committee D26 on
Halogenated Organic Solvents and Fire Extinguishi
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