Standard Test Method for Bromine in Chlorine

SIGNIFICANCE AND USE
Low levels of bromine contaminant in chlorine cause problems in some industrial uses. This test method may be used to determine bromine in liquid or gaseous chlorine at levels as low as 4 ug/kg.
SCOPE
1.1 This test method covers the determination of bromine in liquid chlorine and in gaseous chlorine with a lower limit of detection of 4 ug/kg by weight.
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. Specific hazard statements are given in Section 7.
1.3 Review the current Materials Safety Data Sheets (MSDS) for detailed information concerning toxicity, first-aid procedures, handling, and safety precautions.

General Information

Status
Historical
Publication Date
31-Jul-2011
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM E649-00(2011) - Standard Test Method for Bromine in Chlorine
English language
5 pages
sale 15% off
Preview
sale 15% off
Preview

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: E649 − 00 (Reapproved 2011)
Standard Test Method for
Bromine in Chlorine
This standard is issued under the fixed designation E649; 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 bromate is reduced to bromide by iodide, and the liberated
iodine is titrated with standard sodium thiosulfate solution.
1.1 This test method covers the determination of bromine in
liquid chlorine and in gaseous chlorine with a lower limit of
4. Significance and Use
detection of 4 ug/kg by weight.
4.1 Low levels of bromine contaminant in chlorine cause
1.2 This standard does not purport to address all of the
problems in some industrial uses. This test method may be
safety concerns, if any, associated with its use. It is the
used to determine bromine in liquid or gaseous chlorine at
responsibility of the user of this standard to establish appro-
levels as low as 4 ug/kg.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. Specific hazard
5. Apparatus
statements are given in Section 7.
1.3 Review the current Materials Safety Data Sheets
5.1 The construction of the chlorine gas sampling apparatus
(MSDS) for detailed information concerning toxicity, first-aid
and of the assembled sampling equipment is shown in Figs. 1
procedures, handling, and safety precautions.
and 2. Modification of the equipment to deal with special
sampling circumstances may be necessary. In Fig. 2, the
2. Referenced Documents
control valve is shown with an adaptor for connection to a
chlorine cylinder valve. Other adaptors will be required when
2.1 ASTM Standards:
sampling liquid chlorine in liquefaction plant streams or from
D1193 Specification for Reagent Water
large shipping or storage containers.
E180 Practice for Determining the Precision of ASTM
Methods for Analysis and Testing of Industrial and Spe-
5.2 A 10-mL buret calibrated in 0.05-mL divisions is used
cialty Chemicals (Withdrawn 2009)
when titrating with 0.01 N standard sodium thiosulfate solu-
E200 Practice for Preparation, Standardization, and Storage
tion.
of Standard and Reagent Solutions for ChemicalAnalysis
6. Reagents
3. Summary of Test Method
6.1 Purity of Reagents—Unless otherwise indicated, it is
3.1 Chlorine gas is sampled by absorption in aqueous
intended that all reagents should conform to the specifications
sodium hydroxide (NaOH). Liquid chlorine is first vaporized,
of the Committee on Analytical Reagents of the American
and the vapor is absorbed in aqueous sodium hydroxide. An
Chemical Society, where such specifications are available.
aliquot of the sample solution is reduced with an excess of
Other grades may be used, provided it is first ascertained that
sulfite ion, acidified, and excess sulfur dioxide (SO ) boiled
the reagent is of sufficiently high purity to permit its use
out. In a carefully buffered solution, bromide is oxidized to
without lessening the accuracy of the determination.
bromate by hypochlorite. Excess hypochlorite is reduced to
6.2 Purity of Water—Unless otherwise indicated, references
chloride by formate. In the presence of molybdate catalyst,
to water shall be understood to mean Type II or Type III
reagent water conforming to Specification D1193.
This test method is under the jurisdiction of ASTM Committee D16 on
6.3 Chloride Solution—Dissolve 200 g of sodium chloride
Aromatic Hydrocarbons and Related Chemicals and is the direct responsibility of
(NaCl) in 940 mL of water.
Subcommittee D16.16 on Industrial and Specialty Product Standards.
Current edition approved Aug. 1, 2011. Published November 2011. Originally
ε1
approved in 1978. Last previous edition approved in 2005 as E649 – 00 (2005) .
DOI: 10.1520/E0649-00R11.
2 4
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Reagent Chemicals, American Chemical Society Specifications, American
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Chemical Society, Washington, DC. For suggestions on the testing of reagents not
Standards volume information, refer to the standard’s Document Summary page on listed by the American Chemical Society, see Analar Standards for Laboratory
the ASTM website. Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
The last approved version of this historical standard is referenced on and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
www.astm.org. MD.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E649 − 00 (2011)
FIG. 1 Chlorine Gas Sampling Apparatus
1. Inverted liquid chlorine cylinder
2. Chlorine cylinder valve
3. Control valve ( ⁄4-in. 316 stainless steel needle valve)
4. ⁄4-in. PTFE instrument air tubing
5. Small pail or 2-L beaker filled with water
6. Evaporating coil (two loops held with tape at indicated points)
7. Gas sampling apparatus of Fig. 1
FIG. 2 Liquid Chlorine Sampling Equipment
E649 − 00 (2011)
6.4 Formate Solution—Dissolve 50 g of sodium formate in area. In sampling liquid chlorine, do not leave the space
175 mL of water. between two closed valves filled with liquid chlorine (see 8.6).
6.5 Hypochlorite Solution—Dissolve 6.2 g of NaOH in 190 7.3 When sampling and working with chlorine out of doors,
mLof water and chlorinate slowly, with stirring, to give a gain people downwind from such operation should be warned of the
in weight of 5.0 g. possible release of chlorine vapors.
7.4 It is recommended that means be available for disposal
NOTE 1—If desired, a commercial hypochlorite bleach solution may be
used as the hypochlorite solution. Although such commercial bleach
of excess chlorine in an environmentally safe and acceptable
solutions are not made from reagent grade chemicals, the reagent blank
manner. If chlorine cannot be disposed of in a chlorine-
determination (see 9.4) corrects for the bromine and any chlorate content
consuming process, a chlorine absorption system should be
in such solutions. A proprietary 5.25 % sodium hypochlorite bleach
provided. When the analysis and sampling regimen requires an
solution is satisfactory for this use. Because the sodium chloride and
initialpurgingofchlorinefromacontainer,thepurgedchlorine
hypochlorite solutions contribute most to the reagent blanks, dispense
these solutions by pipet to ensure uniformity of blanks and determinations
should be similarly handled. Purging to the atmosphere should
(see 9.1 and 9.2).
be avoided.
6.6 Molybdate Solution (44 g/L)—Dissolve 4.4 g of ammo-
7.5 In the event chlorine is inhaled, first aid should be
nium molybdate (NH ) Mo O ·4H O) in 10 mL of 6 N
4 6 7 24 2
summoned immediately and oxygen administered without
ammonium hydroxide (NH OH) and dilute with 90 mL of
delay.
water.
7.6 Chlorine is a corrosive and toxic material. A well-
6.7 Phenolphthalein Indicator Solution (1 g/L)—Dissolve
ventilated fume hood should be used to house all test equip-
0.1 g of phenolphthalein and 0.1 g sodium carbonate (Na CO )
2 3
ment when this product is analyzed in the laboratory.
in 5 mL of water and dilute to 100 mL.
6.8 Phosphate Solution (100 g/L)—Dissolve 50 g of
8. Sampling
monobasic sodium phosphate (NaH PO ·H O) in 500 mL of
2 4 2
8.1 Record to the nearest 0.1 g the tare of the clean and dry
water.
chlorine gas sampling apparatus of Fig. 1, except for the
6.9 Sodium Hydroxide Solution (10 %)—Dissolve 1 part by
insulatingjacket.Add150mLof10 %NaOHsolutionandseal
weight of sodium hydroxide (NaOH) in 9 parts of water.
the stopper firmly in place. Record the tare of this assembly to
the nearest 0.1 g. Place the apparatus in the insulating jacket
6.10 Sodium Thiosulfate, Standard Solution (0.01 N)—
and allow to stand to reach temperature equilibrium.
Prepare 0.01 N sodium thiosulfate solution fresh daily by
accurate dilution of standard 0.1 N sodium thiosulfate solution.
8.2 Saturated chlorine vapor will contain only about 0.3 as
Prepare, standardize, and restandardize 0.1 Nsodium thiosul-
much bromine as the liquid chlorine with which it is in
fate solution in accordance with Practice E200.
equilibrium. Hence, when sampling containers of liquid
chlorine, it is necessary to make sure that only the liquid phase
6.11 Starch Solution (10 g/L)—Dissolve1gof soluble
is sampled. Gaseous chlorine sources may be sampled directly,
starch in 100 mL of boiling water. Make up fresh daily.
using a small valve to control the chlorine flow. Feed the liquid
6.12 Sulfuric Acid (6 N)—Add slowly and cautiously with
chlorine through vaporizing equipment before passing the
constant stirring, 1 volume of concentrated sulfuric acid (sp gr
resulting vapor into the chlorine gas sampling apparatus.There
1.84, H SO ) to 5.5 volumes of water. Warning: Use goggles
2 4
is no need for a vaporizer when sampling a source of gaseous
when preparing this solution. Cool to room temperature before
chlorine.
use.
8.3 A satisfactory vaporizer for sampling liquid chlorine is
6.13 Sulfuric Acid (1+1)—Add slowly with stirring 1
readily prepared from a 1.5 to 2-m length of ⁄4-in. (6.35-mm)
volume of concentrated sulfuric acid (H SO , sp gr 1.84) to 1
2 4
outside diameter polytrafluoroethylene (PTFE) instrument air
volume of water. Warning: Use goggles when preparing this
tubing. This had adequate flexibility, and is easily coiled to
solution.
form a 120-mm diameter evapora
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.