ASTM_D_3972_-_09_2015.pdf

Designation:D397209(Reapproved 2015)Standard Test Method forIsotopic Uranium in Water by Radiochemistry1This standard is issued under the fixed designation D3972;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 alpha-particle-emitting isotopes of uranium in water by means ofchemical separations and alpha pulse-height analysis(alsoknown as alpha-particle spectrometry).Uranium is chemicallyseparated from a water sample by coprecipitation with ferroushydroxide,anion exchange,and electrodeposition.The testmethod applies to soluble uranium as well as to any uraniumthat might be present in suspended matter in the water sample.This test method is applicable for uranium processing effluentsas well as substitute ocean water.When suspended matter ispresent,an acid dissolution step is added to assure that all ofthe uranium dissolves.It is the users responsibility to ensurethe validity of this test method for waters of untested matrices.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.Specific warningstatements are given in Section 9.2.Referenced Documents2.1 ASTM Standards:2C859 Terminology Relating to Nuclear MaterialsC1163 Practice for Mounting Actinides for Alpha Spectrom-etry Using Neodymium FluorideD1066 Practice for Sampling SteamD1129 Terminology Relating to WaterD1192 Guide for Equipment for Sampling Water and Steamin Closed Conduits(Withdrawn 2003)3D1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD3084 Practice for Alpha-Particle Spectrometry of WaterD3370 Practices for Sampling Water from Closed ConduitsD3648 Practices for the Measurement of RadioactivityD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water AnalysisD7282 Practice for Set-up,Calibration,and Quality Controlof Instruments Used for Radioactivity Measurements3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this test method,referto Terminologies C859 and D1129.For terms not included inthese reference may be made to other published glossaries.4,54.Summary of Test Method4.1 The water sample to be analyzed is acidified and232U isadded to serve as an isotopic tracer before any additionaloperations are performed.If the sample is a seawater sample,or if it contains carbonate or bicarbonate ions,the sample mustbe boiled under acidic conditions to convert these ions tocarbon dioxide gas which is then expelled from the solution.Carbonate ions must not be present during the precipitationstep because they complex the uranium and prevent itscoprecipitation.The uranium is coprecipitated from the samplewith ferrous hydroxide.This precipitate is dissolved in con-centrated hydrochloric acid,or is subjected to an acid dissolu-tion with concentrated nitric and hydrofluoric acids if thehydrochloric acid fails to dissolve the precipitate.4.2 The uranium is separated from other radionuclides byadsorption on anion-exchange resin from 8 M hydrochloricacid,followed by elution with 0.1 M hydrochloric acid.Theuranium is electrodeposited onto a stainless steel disk.Isotopicuranium radioactivities are measured by alpha pulse-height1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.04 on Methods of Radiochemi-cal Analysis.Current edition approved Jan.1,2015.Published January 2015.Originallyapproved in 1980.Last previous edition approved in 2009 as D3972 09.DOI:10.1520/D3972-09R15.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.4Parker,S.P.,ed.,Dictionary of Chemical Terms,McGraw-Hill Book Co.,NewYork,NY,1985.5IUPAC,“Glossary of Terms Used in Nuclear Analytical Chemistry,”Pure andApplied Chemistry,Vol 54,1982,pp.15331554.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 analysis with a silicon surface-barrier or ion-implanted detectorand a multichannel analyzer.4.3 When232U is used as the tracer,the other isotopes ofuranium listed in Table 1 can be detected in the alpha-particlespectrum