1、Designation:D475595(Reapproved 2020)Standard Test Method forFree Halogens in Halogenated Organic Solvents and TheirAdmixtures1This standard is issued under the fixed designation D4755;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,t
2、he year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the evaluation of free halogensin halogenated organic solvents and their admixtures.1.2
3、The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate
4、 safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment
5、of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent Water3.Summary of Test Method3.1 Any free halogens present in the halogenated solvent areex
6、tracted with water and reacted with potassium iodide testsolution containing starch indicator.A blue color indicates thatpresence of free halogens.4.Significance and Use4.1 Free halogens will react with any residual moisture in asolvent to form acid.These acids can cause corrosion toprocess and stor
7、age equipment used for halogenated solvents.4.2 The presence of free halogens in halogenated solvents isoften an indication that the stabilizers in the solvent system arebreaking down.4.3 This test method provides a means of detecting thepresence of free halogens in halogenated solvents and theiradm
8、ixtures.5.Interferences5.1 The following materials interfere with this test giving afalse positive:ferric ion;phosgene;iodine;oxidizing agents;and strong acid(catalyze atmospheric oxidation of the KI).6.Apparatus6.1 Glass-Stoppered Graduate,25 mL.7.Reagents7.1 Purity of ReagentsReagent grade chemica
9、ls shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused,provided it is first ascertained that
10、 the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.7.2 Purity of WaterUnless otherwise indicated,referencesto water shall be understood to mean reagent water conformingto Type III of Specification D1193.7.3 Potassium Iodide(KI)Test Solutio
11、nDissolve 16.5 g ofpotassium iodide in water to make 100 mL.Store in light-resistant containers.7.4 Starch Test SolutionMix 1 g of soluble starch4with 10mg of red mercuric iodide and sufficient cold water to make athin paste.Add 200 mL of boiling water,and boil for 1 minwith continuous stirring.Cool
12、,and use only the clear solution.1This test method is under the jurisdiction of ASTM Committee D26 onHalogenated Organic Solvents and Fire Extinguishing Agents and is the directresponsibility of Subcommittee D26.04 on Test Methods.Current edition approved April 1,2020.Published April 2020.Originally
13、approved in 1987.Last previous edition approved in 2015 as D475595(2015)1.DOI:10.1520/D475595R20.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document S
14、ummary page onthe ASTM website.3Reagent Chemicals,American Chemical Society Specifications,AmericanChemical Society,Washington,DC.For suggestions on the testing of reagents notlisted by the American Chemical Society,see Analar Standards for LaboratoryChemicals,BDH Ltd.,Poole,Dorset,U.K.,and the Unit
15、ed States Pharmacopeiaand National Formulary,U.S.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.4Commercially available,stabilized starch indicator solutions may be used.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international s
16、tandard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.8.Procedure8.1 Transfer 10 mL of sample to a glass-stoppered graduateand add 10 mL of potassium iodide test solution and 1 mL ofstarch indicator solution.Shake vigorously for 2 min andobserve color of the a
