Tsvetomil VOYSLAVOV, Sonya GANEVA, Stefan TSAKOVSKI

Determination of hexavalent chromium in aqueous and alkaline soil extracts

A fast, simple, and reliable method for determination of hexavalent chromium species in soil aqueous andalkaline extracts has been developed. The procedure is based on the ion-pair extraction of Cr(VI) with methyltrioctylam-monium chloride (Aliquat 336) into xylene. The extract is analyzed by ame (FAAS) or electrothermal atomic absorptionspectrometry (ETAAS). The method allows the detection of up to 2 mg kg1Cr(VI) by FAAS and up to 25 g kg1Cr(VI) by ETAAS. The relative standard deviation varied in the range 2%{12% depending on the Cr(VI) levels in thesamples. The analysis of certi ed reference material CRM041-30G Chromium VI{Soil and spike experiments showedrecoveries from 91% to 106%. The procedure was applied to industrially polluted soils.

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