1、Designation:D525802(Reapproved 2013)Standard Practice forAcid-Extraction of Elements from Sediments Using ClosedVessel Microwave Heating1This standard is issued under the fixed designation D5258;the number immediately following the designation indicates the year oforiginal adoption or,in the case of
2、 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 digestion of soils and sedimentsfor subsequent determination of acid-extract
3、able concentra-tions of certain elements by such techniques as atomic absorp-tion and atomic emission spectroscopy.1.1.1 Concentrations of arsenic,cadmium,copper,lead,magnesium,manganese,nickel,and zinc can be extracted fromthe preceding materials.Other elements may be determinedusing this practice.
4、1.2 The analytical sample is arbitrarily defined as that whichpasses a 10-mesh(approximately 2-mm openings)screen andis prepared according to Practice D3974.1.3 Actual element quantitation can be accomplished byfollowing the various test methods under other appropriateASTM standards for element(s)of
5、 interest.1.4 The detection limit and linear concentration range foreach element is dependent on the atomic absorption or emis-sion spectrophotometric technique employed and may be foundin the manual accompanying the instrument used.1.5 Before selecting a digestion technique,the user shouldconsult t
6、he appropriate quantitation standard(s)for any specialanalytical considerations,and Practice D3974 for any specialpreparatory considerations.1.6 The extent of extraction of elements from soils andsediments by this method is dependent upon the physical andmineralogic characteristics of the prepared s
7、ample.1.7 The values stated in both inch-pound and SI units are tobe regarded separately as the standard.The values given inparentheses are for information only.1.8 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user
8、of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.For specific hazardstatements,see Section 8.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD3974 Practices for Extraction of
9、Trace Elements fromSediments2.2 Code of Federal Regulations:3CFR Title 21,Part 1030,and Title 47,Part 183.Summary of Practice3.1 The chemical portion of this practice involves aciddigestion to dissociate the elements not interstitially bound insilicate lattices.3.2 The sample is digested with nitric
10、 acid in a closedfluoropolymer vessel using microwave heating to an internalpressure of 100 psi(6.89 106dynes/cm2).3.3 This practice provides a sample suitable for analysis byatomic absorption or emission spectrophotometry.4.Significance and Use4.1 Partial extraction of soils and sediments can provi
11、deinformation on the availability of elements to leeching,waterquality changes,or other site conditions.4.2 Rapid heating,in combination with temperatures inexcess of the atmospheric boiling point of nitric acid,reducessample preparation or reaction times.4.3 Little or no acids are lost to boiling o
12、r evaporation in theclosed digestion vessel so additional portions of acid may notbe required.Increased blank corrections from trace impuritiesin acid are minimized.1This practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.07 on Sedim
13、ents,Geomorphology,and Open-Channel Flow.Current edition approved Jan.1,2013.Published January 2013.Originallyapproved in 1992.Last previous edition approved in 2007 as D5258 02(2007).DOI:10.1520/D5258-02R13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer S
14、ervice at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk,DODSSP,Bldg.4,SectionD,700RobbinsAve.,Philadelphia,PA19111-5098,http:/www.dodssp.daps.mil.Copyright ASTM
15、International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Interferences5.1 No interferences to the digestion of soils and sedimentsusing microwave heating have been observed.5.2 Precautions should be exercised to avoid those interfer-ences normally associated w
16、ith the final determination ofelements using atomic absorption or emission spectroscopy.6.Apparatus6.1 Microwave Heating SystemA laboratory microwaveheating system capable of delivering a minimum of 570 W ofmicrowave energy.The system should be capable of 1%power adjustments and 1 s time adjustment.The microwavecavity should be fluoropolymer coated and equipped withexhaust ventilation sufficient to provide ten chamber exchangesper minute.The cavity must have a 360 oscillating turntable toensure
