Specific Procedure for Metal Solid Speciation in Heavily Polluted River Sediments

Abstract

Sequential extraction schemes are used in determining the partitioning of trace metals in sediments. Among them the most widely used is that proposed by Tessier et al.⁵ A modified Tessier procedure, with successive extractions until completeness is attained, using pH control for extraction of metal solubilized by acetic acid-acetate buffer, control of extracted iron and manganese for metal extracted by hydroxylamine hydrochloride and control of redox potential (Eh) of extractant solution for metal solubilized by hydrogen peroxide, is proposed for copper, lead, chromium and nickel speciation. The results obtained with the initial Tessier procedure and those obtained with the modified procedure are compared with a heavily polluted sediment sample, and the resulting metal distributions are discussed.