Determination of Zinc Species Using Ultrafiltration and Different Solid Sorbents

Abstract: A method for the determination of operationally-defined metal species at natural concentration levels has been developed. The method is based on a combination of physical characterization by size fractionation using ultrafiltration and chemical characterization by retention studies on different solid sorbents. The aim of this study is to investigate the effect of pH on its performance. A set of three columns packed with different sorbents, namely, cation-exchange resin Chelex-100, anion-exchange resin Dowex 1-X8 and C-18 reversed phase was developed. The retention of metal species in each size fraction onto the sorbents at different pH conditions was investigated. Experiments were performed with metals in the presence of model ligands, namely, nitrilotriacetic acid (NTA), ethylenediamine tetraacetic acid (EDTA), humic acid (HA), 8-hydroxyquinoline-5-sulphonic acid (SOX) and 8-hydroxyquinoline (OX). The applicability of the method was investigated using synthetic river water samples spiked with species of zinc.