Speciation of Cr(III) and Cr(VI) in Environmental Water Determined by Selective Separation and Preconcentration on the PBST-RSP

Abstract

In this paper, a new method for the speciation, separation and preconcentration of Cr(VI) and Cr(III) in water was developed.The procedure presented based on two forms of chromium show different adsorption capacities on the Porous nano-barium strontium titanate by reversed-phase suspension polymerization and sol-gel method (PBST-RSP) at different pH values, that is, Cr (VI) selectively retained at pH 1-2, but Cr(Ⅲ) can't be adsorbed.Whereas Cr (III) retained at pH 7-14, but Cr(VI) can't be adsorbed.Hence complete separation of the Cr(VI) and Cr(III) is possible.Retained Cr(VI) and Cr(III) were eluted with 1 mol/L HCl and 1 mol/L NaOH, respectively.The Cr(VI) and Cr(III) concentration were measured by flame atomic absorption spectrometer.The method was successfully applied for the speciation of chromium in surface water and drinking water samples with successfully results.