ASTM_E_1070_-_11.pdf

Designation:E107011Standard Test Method forDetermination of Phosphorus in Iron Ores by Phospho-Molybdenum-Blue Spectrophotometry1This standard is issued under the fixed designation E1070;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 covers the determination of phospho-rus in iron ores,concentrates,and agglomerates in the concen-tration range from 0.005 to 1.0%phosphorus.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 test method has been evaluated in accordance withPractice E1601 and Guide E1763.Unless otherwise noted inthe precision and bias section,the lower limit in the scope ofeach method specifies the lowest analyte content that may beanalyzed with acceptable error(defined as a nominal 5%riskof obtaining a 50%or larger relative difference in results onthe same test sample in two laboratories).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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterE50 Practices for Apparatus,Reagents,and Safety Consid-erations for Chemical Analysis of Metals,Ores,andRelated MaterialsE60 Practice for Analysis of Metals,Ores,and RelatedMaterials by SpectrophotometryE135 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 CompositionE882 Guide for Accountability and Quality Control in theChemical Analysis LaboratoryE1601 Practice for Conducting an Interlaboratory Study toEvaluate the Performance of an Analytical MethodE1763 Guide for Interpretation and Use of Results fromInterlaboratory Testing of Chemical Analysis Methods3.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,refer to Terminology E135.4.Summary of Test Method4.1 The sample is fused in a zirconium crucible with sodiumperoxide.The melt is dissolved in water and hydrochloric acid.In a suitable aliquot,the molybdenum blue complex is formedby the addition of ammonium molybdate-hydrazine sulfatesolution.The absorbance of the phospho-molybdenum-bluecomplex is measured at 725 nm.5.Significance and Use5.1 This test method for the analysis of iron ore concentratesand agglomerates is primarily intended as a referee method totest for compliance with compositional specifications.It isassumed that users of this test method will be trained analystscapable of performing common laboratory procedures skill-fully and safely.It is expected that work will be performed ina properly-equipped laboratory and that proper waste disposalprocedures will be followed.Appropriate quality control prac-tices shall be followed,such as those described in Guide E882.5.2 The determination of this element is needed for inter-national trade and primary iron and steel making.6.Interferences6.1 Elements normally found in iron ores do not interfereexcepting arsenic giving positive interference(0.01%As=0.001%P).7.Apparatus7.1 Zirconium Crucible,50 mL capacity.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 E01.02 on Ores,Concentrates,and Related Metal-lurgical Materials.Current edition approved Sept.1,2011.Published September 2011.Originallyapproved in 1985.Last previous edition approved in 2005 as E1070 00(2005).DOI:10.1520/E1070-11.2For 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 7.2 SpectrophotometerVisible spectrophotometer capableof measuring absorbance at the 725 nm wavelength using a1-cm path length cell in accordance with Practice E60.8.Reagents and Materials8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society,wheresuch specifications are available.3Other grades may be used,provided it is first ascertained that the reagent is of sufficienthigh purity to permit its use without lessening the accuracy ofthe determination.8.2 Purity of WaterUnless otherwise indicated,referencesto water shal