ASTM_E_1771_-_07.pdf

Designation:E177107Standard Test Method forDetermination of Copper in Anode and Blister Copper1This standard is issued under the fixed designation E1771;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,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 test method describes the electrolytic determinationof copper in commercial anode(99.0 to 99.8%)and blistercopper(92.0 to 98.0%).1.2 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 safety and health practices and determine the applica-bility of regulatory limitations prior to use.Specific hazardsstatements are given in Section 9.2.Referenced Documents2.1 ASTM Standards:2E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE53 Test Method for Determination of Copper in UnalloyedCopper by GravimetryE135 Terminology Relating to Analytical Chemistry forMetals,Ores,and Related MaterialsE255 Practice for Sampling Copper and Copper Alloys forthe Determination of Chemical CompositionE478 Test Methods for Chemical Analysis of Copper AlloysE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 DefinitionsFor definitions and terms used in this testmethod,refer to Terminology E135.4.Summary of Test Method4.1 After dissolution of the sample,the solution is evapo-rated to dryness and fumes expelled by heat.The salt isdissolved in nitric acid,the solution is filtered,the acidity isadjusted,and the copper is electrolytically plated and weighedas the metal.5.Significance and Use5.1 This test method for the determination of copper inanode(99.0 to 99.8%)and blister copper(92.0 to 98.0%)isprimarily intended as a referee method,to test such materialsfor compliance with compositional specifications.It is assumedthat users of this test method will be trained analysts capable ofperforming common laboratory procedures skillfully andsafely.It is expected that work will be performed in a properlyequipped laboratory.5.2 This test method is intended to determine the coppercontent of commercial anode and blister copper.Those ele-ments that interfere are removed by precipitation orvolatilization,or both.Copper is electrodeposited as the metaland weighed.5.3 This method will also be found useful for the electro-lytic determination of copper in some copper alloys and scrap.6.Interferences6.1 Commonly present elements,which co-deposit or par-tially co-deposit with copper are precipitated,(for example,silver as the chloride),or volatilized,(for example,antimony,arsenic,selenium),as metal bromides.Molybdenum also willco-deposit with copper to produce a dark plate.When less then6 mg is present,the addition of 1 mg of sodium chloride willprevent deposition.6.2 This test method does not address interferences causedby tungsten and bismuth.7.Apparatus7.1 Electrodes for Electroanalysis7.1.1 ElectrodesRecommended stationary type platinumelectrodes are described in 7.1.2 and 7.1.3.The surface of theplatinum electrodes should be smooth,clean,and bright topromote uniform deposition and good adherence.Deviationsfrom the exact size and shape are allowable.In instances whereit is desirable to decrease the time of deposition and agitationof the electrolyte is permissible,a generally-available rotatingtype of electrode may be employed.Cleaning of the electrolyteby sandblasting is not recommended.1This test method is under the jurisdiction of ASTM Committee E01 onAnalytical Chemistry for Metals,Ores,and Related Materials and is the directresponsibility of Subcommittee E01.05 on Cu,Pb,Zn,Cd,Sn,Be,their Alloys,andRelated Metals.Current edition approved Feb.1,2007.Published February 2007.Originallyapproved in 1995.Last previous edition approved in 2001 as E1771 95(2001).DOI:10.1520/E1771-07.2For 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 Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 7.1.2 CathodesPlatinum cathodes may be either open orclosed cylinders formed from sheets that are plain orperforated,or from gauze.Gauze cathodes are recommended;preferably from 50-mesh gauze woven from approximately0.21 mm(0.0085 in.)diameter wire.The top and bottom ofgauze cathodes should be reinforced by doubling the gauzeabout 3 mm onto itself,or by the use of platinum bands orrings.The cylinder should be approximately 30 mm in diam-eter and 50 mm in height.The stem should be made from aplatinum alloy wire such as platinum-iridium,platinum-rhodium or p