Speciation of chromium using reversed phase-high performance liquid chromatography coupled to different spectrometric detection methods

Abstract

Speciation of Cr(III) and Cr(VI) based on the formation of different complexes with ammonium-pyrrolidinedithioate (APDC) in a continuous flow technique and their preconcentration using solid phase extraction (SPE) have been elaborated and applied to the analysis of waste waters from the galvanic industry. The Cr complexes were separated and determined using reversed phase-high performance liquid chromatography (RP-HPLC) coupled to different detection methods, namely UV-detection, graphite furnace-atomic absorption spectrometry (GF-AAS) and inductively coupled plasma mass spectrometry with hydraulic high pressure nebulization (HHPN/ICP-MS). After optimization the detection limits for Cr(III) and Cr(VI) of all methods are at the μg 1 −1 level and the precision in terms of RSD is 5% ( c Cr = 100 μg 1 −1, N = 10). The procedure was applied to the determination of Cr(III) and Cr(VI) at the μg 1 −1 level in galvanic waste waters, and its accuracy was approved by comparing the results with those of independent methods.