ASTM_D_1246_-_16.pdf

Designation:D124616Standard Test Method forBromide Ion in Water1This standard is issued under the fixed designation D1246;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This test method is applicable to the measurement ofbromide ion in water,ground water,and drinking water.1.2 Samples containing 0.5 mg/L to 1000 mg/L of bromidemay be analyzed by this test method.The concentration rangemay be extended by the dilution of an appropriate aliquot.1.3 The precision and bias statements were determined onnatural and ground waters.It is the responsibility of the analystto assure the validity of this test method for untested matrices.1.4 A titrimetric and two colorimetric test methods foriodide and bromide were discontinued.Refer to Appendix X1for historical information.1.5 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.6 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:2D1066 Practice for Sampling SteamD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD3370 Practices for Sampling Water from Closed ConduitsD4127 Terminology Used with Ion-Selective ElectrodesD5810 Guide for Spiking into Aqueous SamplesD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water Analysis3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard,refer toTerminologies D1129 and D4127.4.Summary of Test Method4.1 Bromide ion is measured potentiometrically using abromide ion-selective electrode in conjunction with a single-junction,sleeve-type reference electrode.Potentials are read ona pH meter having an expanded millivolt scale capable of beingread to the nearest 0.1 mV,or a selective ion meter having adirect concentration scale for bromide.For less precise work,apH meter having a millivolt scale capable of being read to thenearest 1.0 mV is adequate,however,no supporting data areavailable.4.2 The electrodes are calibrated in known bromide solu-tions and the concentrations of unknowns are determined insolutions with the same background.In most cases,addition ofan ionic strength adjustor to both standards and samples issufficient to maintain constant background ionic strength.Forsamples above 0.1 M in ionic strength,prepare standardsolutions similar to the sample composition.5.Significance and Use5.1 By analysis for bromide in water,wastewater,andbrackish waters,it is possible to evaluate the origin of thewater,its potential as a source of bromide,and its conditionwith regard to pollution.6.Interferences6.1 Strongly reducing solutions and solutions containingions which form insoluble silver salts may coat the electrodemembrane.These may be removed by polishing the membranesurface.Sulfide ion and cyanide ion both poison the electrode,and should be removed(see Section 11).6.2 Halide ions form complexes with some metals.Sincethe electrode responds only to free bromide ions,the presenceof any complexing agents lowers the measured concentrations.Concentrations of free metal ions causing a 10%error of a1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.05 on Inorganic Constituentsin Water.Current edition approved June 15,2016.Published June 2016.Originallyapproved in 1952.Last previous edition approved in 2010 as D1246 10.DOI:10.1520/D1246-16.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 bromide concentration of 8.1 mg/L are bismuth+3,80 mg/L;cadmium+2,100 mg/L;lead+2,1600 mg/L;tin+2,2400 mg/L;and thallium+3,4 mg/L.6.3 Chloride ion and hydroxide ion do not interfere whenpresent in the concentrations of up to 400 and 30 000 times thebromide concentration,respectively.There will be no interfer-ence from ammonia when present in concentrations twice thatof bromide,nor from thiosulfate 20 times as concentrated asbromide.Iodide is an interference at a concentration ra