Extractive separation and determination of chromium in tannery effluents and electroplating waste water using tribenzylamine as the extractant

A simple extractive separation method has been developed for the determination of chromium based on the extraction of Cr (VI) as its ion-pair with tribenzylamine (TBA). The ion-pair is extracted at acidic pH using toluene as the diluent. The concentration of chromium in the organic phase was measured spectrophotometrically at 309 nm. The influence of experimental variables such as pH, sample Volume, equilibration time, diverse ions etc. has been studied in detail. The extracted chromium (VI) could be stripped to the aqueous phase using NaOH as the stripping agent. The extracts were characterized using FT-IR spectroscopy. A detection limit of 0.08 mu gmL(-1) could be achieved and the validity of the method was checked in real tannery effluent, electroplating waste water and spiked water samples. (C) 2008 Elsevier B.V. All rights reserved.