ASTM_E_2293_-_03_2013.pdf

Designation:E229303(Reapproved 2013)Standard Practice forDrying of Metal Bearing Ores,Concentrates,and RelatedMetallurgical Materials for the Determination of Mercury1This standard is issued under the fixed designation E2293;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 practice covers the sample drying step for thedetermination of mercury in ores,concentrates,and relatedmetallurgical materials.1.2 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 safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E50 Practices for Apparatus,Reagents,and Safety Consid-erations for Chemical Analysis of Metals,Ores,andRelated MaterialsE135 Terminology Relating to Analytical Chemistry forMetals,Ores,and Related MaterialsE877 Practice for Sampling and Sample Preparation of IronOres and Related Materials for Determination of Chemi-cal Composition and Physical PropertiesE882 Guide for Accountability and Quality Control in theChemical Analysis Laboratory2.2 Other Documents:3ISO 9599 Copper,Lead,and Zinc Sulfide ConcentratesDe-termination of Hygroscopic Moisture in the AnalysisSample-Gravimetric MethodISO 12743 Copper,Lead,and Zinc Sulfide ConcentratesSampling Procedures for the Determination of Metal andMoisture ContentISO 10251 Copper,Lead,and Zinc Sulfide ConcentratesDetermination of Mass Loss of Bulk Material on Drying3.Terminology3.1 DefinitionsFor definitions of terms used in thisPractice,refer to Terminology E135.4.Summary of Practice4.1 Test samples for be used for mercury determination aredried at 60 C.5.Significance and Use5.1 This practice is primarily to be used to dry samples forthe determination of mercury test portions,and it should not beused for the determination of sample moisture content.Mostsample preparation methods prescribe drying the samples at105 C,until a constant mass is obtained.The moisture contentis determined as the percentage mass loss on drying.However,since mercury can volatize from samples at the normallyutilized temperature,samples that are to be used for mercurydetermination shall be dried at 60 C(see Practice E877,ISO 9599,ISO 12743,and ISO 10251).5.2 It is assumed that all who use this practice will betrained analysts capable of performing skillfully and safely.Itis expected that work will be performed in a properly equippedlaboratory under appropriate quality control practices such asthose described in Guide E882.6.Apparatus6.1 Drying Oven,ventilated with forced circulation of air,regulated at a temperature of 60 C 6 2 C.6.2 Top-Loading Balance,minimum precision of 0.01%.6.3 Drying Trays,capable of holding at least a 1 kg sample,spread no thicker than 3 cm deep.7.Hazards7.1 For precautions to be observed in this practice,refer toPractices E50.1This practice is under the jurisdiction of ASTM Committee E01 on AnalyticalChemistry for Metals,Ores,and Related Materials and is the direct responsibility ofSubcommittee E01.02 on Ores,Concentrates,and Related Metallurgical Materials.Current edition approved Nov.1,2013.Published December 2013.Originallyapproved in 2003.Last previous edition approved in 2008 as E2293 03(2008)1.DOI:10.1520/E2293-03R13.2For 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.3Available from International Organization for Standardization(ISO),1,ch.dela Voie-Creuse,Case postale 56,CH-1211,Geneva 20,Switzerland,http:/www.iso.ch.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 7.2 Mercury can form vapors at low temperatures.Mercuryvapors can be hazardous to your health.Perform method inventilated areas or wear special health protection equipment.8.Procedure8.1 Remove a representative laboratory sample,500 gminimum,from the gross sample.8.2 Place the laboratory sample into a drying tray and levelto approximately 3 cm.8.3 Weigh to within 0.01 g on the top loading balance.8.4 Place the tray and test portion into the drying oven anddry at 60 C for at least 16 h.NOTE1Once the drying period has commenced,no other wet samplesshould be placed into the same drying oven.8.5 Remove the tray and laboratory sample from the ovenand weigh.Dry the tray and laboratory sample for an additional4 h.Remove from the oven and weigh again.Repeat this stepas necessary until