1、Designation:D337212Standard Test Method forMolybdenum in Water1This standard is issued under the fixed designation D3372;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
2、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 covers the determination of dissolvedandtotalrecoverablemolybdenuminmost
3、waters,wastewaters,and brines by atomic absorption spectroscopy.21.2 This test method is applicable in the range from 1 to 25g/L of molybdenum.The range may be extended by dilutionof the sample.1.3 This test method has been used successfully with naturaland reagent waters.It is the users responsibil
4、ity to ensure thevalidity of this test method for waters of untested matrices.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system are mathematical conversions and may not beexact equivalents;therefore,each system shall
5、 be used inde-pendently of the other.1.5 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 limita
6、tions prior to use.For specificprecautionary statements,see Note 3 and Note 11.2.Referenced Documents2.1 ASTM Standards:3D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD
7、3370 Practices for Sampling Water from Closed ConduitsD4691 Practice for Measuring Elements in Water by FlameAtomic Absorption SpectrophotometryD4841 Practice for Estimation of Holding Time for WaterSamples Containing Organic and Inorganic ConstituentsD5810 Guide for Spiking into Aqueous SamplesD584
8、7 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water Analysis3.Terminology3.1 Definitions:For definitions of terms used in this testmethod,refer to Terminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 laboratory control samplea solution with
9、the certi-fied concentration(s)of the analytes.3.2.2 total recoverable molybdenuman arbitrary analyticalterm relating to the forms of molybdenum that are determin-able by the digestion procedure described in this test method.4.Summary of Test Method4.1 Molybdenum is determined by atomic-absorption s
10、pec-trophotometry.Theelementischelatedwith8-hydroxyquinoline,extracted with methyl isobutyl ketone,and the extract aspirated into the nitrous oxide-acetylene flameof the spectrophotometer.5.Significance and Use5.1 Molybdenum can be found in waste that results fromchemical cleaning of components in w
11、hich the metal is alloyed.5.2 National Pollution Discharge Elimination System(NPDES)permits or other standards,or both,require monitor-ing pollutants in waste discharged onto the water shed of,orinto,navigable waters,and those disposed of in such a mannerthat eventual contamination of underground wa
12、ter could result.5.3 This test method affords an accurate and sensitive meansof determining compliance with those permits.6.Interferences6.1 Vanadium(V)and iron(III)enhance the absorption,while chromium(VI)and tungsten(VI)suppress it.Theseinterferences are eliminated by the addition of ascorbic acid
13、.1This 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 Sept.1,2012.Published October 2012.Originallyapproved in 1975.Last previous edition approved in 2002 as D3372
14、02(2007)1.DOI:10.1520/D3372-12.2Chau,Y.K.,and Lum-Shue-Chan,K.,“Atomic Absorption Determination ofMicrogram Quantities of Molybdenum in Lake Waters,”Analytica Chimica Acta,Vol 48,1969,p.205.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at servicea
15、stm.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 7
16、.Apparatus7.1 Atomic-Absorption Spectrophotometer,for use at 313.3nm.A general guide for the use of flame atomic absorptionapplications is given in Practice D4691.NOTE1The manufacturers instructions should be followed for allinstrumental parameters.7.1.1 Molybdenum Hollow-Cathode Lamp.7.2 Pressure-Reducing ValvesThe supplies of fuel andoxidant shall be maintained at a pressure somewhat higher thanthe controlled operating pressure of the instrument by suitablevalves.8.Reagents and Materials8.1 Pu
