ASTM_D_4183_-_82_scan.pdf

Designation:D 4183-82 4 T b AMERICANSOCIETY FOR TESTING AND MATERIALS 1916 Race St.,Philadelphia,Pa.19103 Reprinted from the Annual Book of ASTM Standards,Copyright ASTM If not listed in the current combined index,will appear in the next edition.Standard Test Mef hods for TOTAL RECOVERABLE PHOSPHORUS AND ORGANIC PHOSPHORUS IN SEDIMENTS Tbis sfandard is issued under the f t x e d designation D 4183;the number immediately following the designation indicates the year of originaladoption or,i n the w e of revision,the year oflast revision.A number i n parentheses indicates the year Qf last reappr0val.A superscript epsilon(E)indicates BD editoriai change since the last revision or reapproval.I.scope 1.1 These methods cover the determination of total recoverable phosphorus and organic phosphorus in sediments.These methods are applicable to ali forms of phosphorus except polyphosphatesand minerais containing tightly bound phosphorus such as manozite and xe-notime(i)?The majority of sediments do not contain significant amounts of fhe above forms of phosphorus and hence the contrbution from these forms is considered to be negible.The analytical range is from 109 to 2000 pg P/g.The range of sample sue for analysis is 0,l to 0.5 g.When concentration of total phosphorus exceeds 2000 pg P/g the range may be extended by appropriate dilution of the sample solution using reagent water.The foliowing methods are included Method A-Manual Colorimetric Sections Sample Preparation 6 to 10 Ascorbic Acid Re-duction Method-Method A,Section 8 to 16 of Method D 5 15 Methods Bi and B-Automated Colorimet-ric Methods UtiUzig Reduction Product of Molybdophosphoric Acid(2)12 to 18 2.Applicable Documeats 2.1 ASTM Standards:D 515 Test Methods for Phosphorus In Wa-D 1129 Definitions of Terms Relating to D 1193 Specification for Reagent Water3 D 3975 Practice for Preparation of Samples For Collaborative Testing of Methods for Analysis of Sediments3 E 60 Recommended Practice for Photomet-ric Methods for Chemical Analysis of Met-ais4 te?wate?E 275 Recommended Practice for Describ-ing Measuring Performance of Spectro-photometers 3.Summary of Methods 3.1 Dry sediments are ignited at 550T for 2 h and the residue after ignition is digested over night at room temperature with 1.0 M hydrochloric acid prior to detemination of the resultant orthophosphate.The orthophosphate concentration measured i n this acid extract is a measure of the toral phosphorus(3,4)content in the sediment.Theinorganic phosphoms con-tent is determined by digesting of the sediment with 1.0 M hydrochloric acid without ignition.The organic phosphorus i s estimated by t a h g the difference between total phosphorus and inorganic phosphorus.3.2 The methods for quantitative estimation of orthophosphate are based on the reaction of ammonium molybdate with orthophosphate to form a molybdophosphate complex.The com-plex is reduced with ascorbic acid to form a blue molybdenum complex.The color intensity is proportional to the phosphorus content.In Method B2,antimony tartrate is added to facil-itate the color formation.4.Significance and Use 4.1 Phosphonis and its compounds are widely distributed throughout the environment.These methods are under the jurisdiction of ASTM Committee D-19 on Water and are the directresponsibility of Subcommittee D19.07 on Methods of Testing of Water-Formed Deposits and the Properties of Water.Current editionapproved Sept.24,1982.PublishedMarch 1983.The boldface numbers i n parenthesmefer to the list of refyenox at the end of this standard.1983 Annual Book of ASTM Standards,Yo1 i 1.01.1982 Annual Book of ASTM Siandard,Part 1 2.1982 Annual Book of ASTM Siandards,Pari 42.1 NOTICE:This standard has either been superseded and replaced by a new version or discontinued.Contact ASTM International(www.astm.org)for the latest information.ASTM Dq383 82 W 0757530 003Li242 7 W Phosphorus plays an important role during the photosynthesis of aquatic macro-and micro-organisms.Phosphorus does not occur as abun-dantly in nature as either carbon or nitrogen.It is generally accepted that phosphorus is the main nutrient that triggers eutrophication.Therefore,it is important to determine phos-phorus in aquatic systems that include bottom sediments.4.2 These methods provide procedures whereby analytical data and comparison of results can be achieved.5.Interferences 5.1 The interferences are of significance in this method occur for the detection of ortho-phosphate.Namely,vanadium,zirconium,ger-manium,sulfide,tannin,lignin and hexavalent chromium interfere when present above 0.5-mg/g levels(5).Arsenic interferes when present in low milligram per kilogram levels.For ex-ample,2.3 mg/kg As provides an interference equivalent to 1 mg/kg P.5.2 See section of Methods D 515 for infor-mation on further interferences.5.3 Since sediments have rather high levels of phosphorus(300 to 3000 pg P/g),interfer-ences from the above metals can be reduced to a minimum by dilution.5.4 The acid concentra