1、Designation:D344810(Reapproved 2015)1Standard Test Method forSpecific Aqueous Conductance of Trichlorotrifluoroethane1This standard is issued under the fixed designation D3448;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year
2、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.1NOTEEditorial changes were made in 1.3 and X1.1 in June 2015.1.Scope1.1 This test method covers the determination of aqueousconduc
3、tivity due to ionizable contaminants extracted fromtrichlorotrifluoroethane.The value of 1.9 S/cm as maximumspecific aqueous conductance corresponds to 0.1 ppm ofchloride ion(100 ppb).It was calculated by putting the solventspecification of 0.1 ppm chloride into the equation of thesubject method to
4、find C2 C1equals 19.08.The specificconductance due to contaminants from the solvent was thencalculated as follows:C22 C1!C3519!0.1!5 1.9 S/cm(1)1.2 The above is exclusive of the background specificconductance of the water used in the analysis.1.3 The values stated in SI units are to be regarded asst
5、andard.No other units of measurement are included in thisstandard.1.3.1 ExceptionValues are stated in inch-pound units inFig.1.1.4 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 consult andest
6、ablish appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.Specific precautionary statements are given in Section 6.2.Summary of Test Method2.1 Ionizable impurities in the solvent are extracted withwater of known low conductivity.The increa
7、se in waterconductivity measures the amount of these impurities present.3.Significance and Use3.1 This test method allows for the determination of ioniz-able contaminants(expressed in terms of ppb of HCl)intrichlorotrifluoroethane via measurement of specific aqueousconductance.3.2 This test method c
8、an be used for establishing manufac-turing and purchasing specifications.4.Apparatus4.1 Conductivity Bridge.24.2 Conductivity Cell,3dip-type.Cell constant of 0.1 recip-rocal centimetre.Electrodes must be bright platinum.4.3 Polyethylene Beaker,250-mL.4.4 Polyethylene Bottles,wide mouth,300-mL and 50
9、0-mLsize.4.4.1 Calibrate and mark the outside of the 300-mL poly-ethylene bottles to indicate 20,120,and 220 mL(graduate)ofwater volume,using deionized water to determine the liquidlevels.4.5 Polyethylene Tubing,long enough to reach the bottomof the 300-mL polyethylene bottle.5.Reagents5.1 Purity of
10、 ReagentsReagent grade chemicals 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.4Other grades may beused,provide
11、d it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.1This test method is under the jurisdiction of ASTM Committee D26 onHalogenated Organic Solvents and Fire Extinguishing Agents and is the directresponsibility
12、 of Subcommittee D26.04 on Test Methods.Current edition approved June 1,2015.Published June 2015.Originallyapproved in 1975.Last previous edition approved in 2010 as D3448 10.DOI:10.1520/D3448-10R15E01.2The sole source of supply of the apparatus(Serfass Model RCM-15B1)knownto the committee at this t
13、ime is Industrial Instrument Inc.,Cedar Grove,NJ.If youare aware of alternative suppliers,please provide this information to ASTMInternational Headquarters.Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.3The sole source of su
14、pply of the apparatus(Model Cel-A01)known to thecommittee at this time is Industrial Instrument Inc.,Cedar Grove,NJ.If you areaware of alternative suppliers,please provide this information to ASTM Interna-tional Headquarters.Your comments will receive careful consideration at a meetingof the respons
15、ible technical committee,1which you may attend.4Reagent 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
16、.K.,and the United States Pharmacopeiaand National Formulary,U.S.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.2 Alcoholic Hydrochloric Acid(0.01 N)Dilute 5.0 mL(pipet)of concentrated hydrochloric acid to 6 L with denatured2B ethyl alcohol.5.3 Alumina Gel.55.4 Deionized Trichloromonofluoromethane,in 25-kg cylin-der.This deionized solvent may be selected pure material or itmay be pur
