1、Designation:D579495(Reapproved 2021)Standard Guide forDetermination of Anions in Cathodic Electrocoat Permeatesby Ion Chromatography1This standard is issued under the fixed designation D5794;the number immediately following the designation indicates the year oforiginal adoption or,in the case of rev
2、ision,the 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 guide is used for the determination of nitrate anionin electrocoat bath permeate by use of chemicall
3、y suppressedand non-suppressed ion chromatography(IC).1.2 Other anions,with the exception of phosphate,may bedetermined in electrocoat bath permeates by use of this guide.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of
4、 the user of this standard to establish appro-priate 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 establish
5、ed in the Decision on Principles for theDevelopment 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.Significance and Use3.1 It is im
6、portant to monitor the anion concentrations andanion contaminants in electrocoat baths.Wet chemical methodsare long,tedious,and of questionable accuracy in the ppmrange.Ion chromatography offers a fast,convenient andaccurate alternative.Since IC analysis of electrocoat bathsamples is difficult,the p
7、ermeates are often analyzed forcontaminants.This guide addresses some important consider-ations for such analyses.4.Apparatus4.1 Awide variety of ion chromatography columns,eluents,and operating parameters are available from commercialsources.The round robin studies conducted in conjunction withthis
8、 guides preparation utilized both suppressed and non-suppressed IC systems,acid and base eluents,strong and weakbase eluents,and varying gradients and flow rates.All labora-tories utilized a conductivity detector for their analysis.4.2 Any properly maintained commercial IC system capableof separatin
9、g,detecting,and quantifying anions by conductiv-ity is deemed satisfactory.5.Guidelines for Analysts5.1 Utilize commercially available ANION standards orprepare anion standards from reagent grade chemicals andreagent water Type I(see Specification D1193).5.2 Sparge all eluent solutions with helium f
10、or at least 15min prior to performing an IC analysis.5.3 When necessary,remove residual traces of organiccompounds such as resin with properly pretreated precolumns.5.4 Utilize at least three standards for calibration.Standardsshould be in the same approximate concentration ranges as theanions conce
11、ntration in the sample.Calibration standardsshould bracket the anions concentration in the sample.5.5 Calibrate instrument only after chromatograms baselineis stable.5.6 Use the peak area for the specific anion of interest asdetermined by an electronic integrator.5.7 Use a sample of sufficient size
12、to completely fill the ionchromatographs injection loop.6.Keywords6.1 cathodic electrocoat;ion chromatography;nitrate;per-meate1This guide is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.21 on
13、 Chemical Analysis of Paints and Paint Materials.Current edition approved Feb.1,2021.Published March 2021.Originallyapproved in 1995.Last previous edition approved in 2014 as D5794 95(2014)DOI:10.1520/D5794-95R21.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Custo
14、mer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in
15、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.1ASTM International takes no po
16、sition respecting the validity of any patent rights asserted in connection with any item mentionedin this standard.Users of this standard are expressly advised that determination of the validity of any such patent rights,and the riskof infringement of such rights,are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised,either reapproved or withdrawn.Your comments are invit