ASTM E1195-2001(2008) 测量土壤和沉积物中有机化学物质吸收常数(Koc)的标准试验方法

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【英文标准名称】:StandardTestMethodforDeterminingaSorptionConstant(Koc)foranOrganicChemicalinSoilandSediments
【原文标准名称】:测量土壤和沉积物中有机化学物质吸收常数(Koc)的标准试验方法
【标准号】:ASTME1195-2001(2008)
【标准状态】:现行
【国别】:美国
【发布日期】:2001
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E47.04
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:equilibriumsorptioncoefficients;partitioningoforganicchemicals;sorptionconstant(Koc);Carbon;Centrifugemethod;Chemicals(environmentalanalysis);Environmentalorganiccompounds;Environmentalsiteasse
【摘要】:Sorptiondataareusefulforevaluatingthemigratorytendencyofchemicalsintotheair,water,andsoilcompartmentsofourenvironment.Theycanbeusedinthepredictionorestimationofvolatilityfromwaterandsoil,concentrationinwater,leachingthroughthesoilprofile,run-offfromlandsurfacesintonaturalwaters,andbiologicalavailability.AdditionalinformationconcerningtestingtodeterminesorptioncoefficientscanbefoundinOECDTestGuideline106(7).Thistestmethodassumesthatsorptionofatleastnonpolarorganicchemicalsismainlyinfluencedbytheorganicmatterofthesoilorsedimentsolids.Thereisampleevidenceintheliteraturetosupportthisassumption,andtheuserofthistestmethodshouldrefertoRef.(2)formoreinformationonthissubject.Organiccarboncontentischosenasthebasisforsorptioninsteadoforganicmattercontent.Thisisbecauseorganiccarbonvaluesgenerallyaremeasureddirectlybyanalyticalmethods.Organicmattermaybeestimatedbymultiplicationoftheorganiccarbonvaluesbyasomewhatarbitraryconstantof1.7(3).Thistestmethodisbasedontheassumptionthatallofthematerialsorbedtothesolidsisreversiblybound.Theanalysesdescribedhereinassumeequilibriumbetweentheliquidandsolidconcentrationsofthetestcompound.Insomecases,theremaybeafractionofthecompoundthatisirreversiblyboundtothesolids.Forthesecases,themeasurementsmadebythetestmaynotreflectatruex201C;equilibriumx201D;.Theirreversiblesorptionphenomenahasbeenextensivelydocumentedandthereaderisreferredto(9),(10)and(8)formorediscussiononthistopic.Asorptionconstantisobtainedandisessentiallyindependentofsoilpropertiesotherthanorganiccarbon.Thisvalueisusefulbecause,onceitisdetermined,thesorptiondistributioncharacteristicsforanysolidcanbeestimatedbasedonitsorganiccarboncontent.Thistestmethodisdesignedtoevaluatesorptionatenvironmentallyrelevantconcentrationsasafunctionoforganiccarboncontentofdifferentsoilandsedimentsolids.Therefore,thenumberofdifferentsolidsisemphasizedintheprocedureratherthanthenumberofchemicalconcentrationsstudiedwitheachsolid.Ingeneral,oneconcentrationisemployedsincethetestmethodassumesthatatlowsolutionconcentrations,sorptionisothermsapproximatelinearityandsorbedconcentrationsdonotexceedtypicalenvironmentalloading.Errorsarisingfromconcentrationeffectsatlowenvironmentalconcentrationsusuallyarelessthanthevariationexistingbetweendifferentsolids,whendealingwithsorptiontrendsinageneralmanner.Therefore,theinitialconcentrationofthetestchemicalinsolutionshouldnotexceed0.5ofitswatersolubility.Asanoption,aprocedureisgivenfordeterminingconcentrationeffectsonsorption.Thisisbecausehighconcentrationsmaybepresentincertainenvironmentalsituations;suchaslandfillsandspills.Thisprocedureshouldbedoneatfourconcentrationsoverahundredfoldconcentrationrange(forexample,0.1,0.5,2,and10ppminitialsolutionconcentration).Iflowsolubilitypresentsanalyticaldifficulties,solutionconcentrationsshouldrangeoveratleastoneorderofmagnitude.TheFreundlichequationisanappropriateexpressionoftheseeffects:where:Ca

【中国标准分类号】:Z18
【国际标准分类号】:13_080_10
【页数】:9P.;A4
【正文语种】:英语