Epichlorohydrin crosslinked chitosan–clay composite beads for on-line preconcentration and determination of chromium(iii) by flow injection flame atomic absorption spectrometry

Abstract

An on-line flow injection preconcentration-flame atomic absorption spectrometry (FI-AAS) method is developed for trace determination of chromium(III) by sorption on a mini-column packed with epichlorohydrin (ECH) crosslinked chitosan–clay composite beads. The factors affecting preconcentration of Cr(III) ions such as sample and eluent flow rate, loading time, sample and eluent pH, and eluent type and concentration were investigated. The Cr(III) ions were eluted from the mini-column with 0.1 M EDTA. Under the optimized parameters, the calibration graph using the preconcentration system for Cr(III) was linear with a correlation coefficient of 0.9982. Detection and quantification limits of the method were obtained to be 0.0162 and 0.0929 μg mL⁻¹ respectively, with an enrichment factor of 13.4.