Simultaneous Photo-Oxidative Degradation of EDTA and Extro-Oxidative Recovery of Copper from Industrial Effluents

The objectives of this investigation are the studies on the effect of copper ion on photolytic degradation of ethylenediaminetertraaceticacid (EDTA), the effect of EDTA on electrolytic recovery of copper as well as the introduction of a novel combined photolytic and electrolytic cell system for simultaneous recovery of copper and the degradation of EDTA.In this experimental study, a photolytic cell, an electrochemical system, and a combined photolytic -electrochemical (photoelectrolysis) system with and without an activated carbon cathode were used. Analysis was carried out using atomic absorption spectroscopy, and high performance liquid chromatography (HPLC).The results show that a single electrochemical cell can be used to recover copper (82.1% after 9 hours) without achieving complete mineralization of EDTA by anodic oxidation (49.9 % after 9 hours). On the other hand a single photolytic cell can achieve 99.9% degradation of EDTA after 9 hours at pH 3.5 but leaves copper in solution. However, a combined photoelectrolytic system using an activated carbon concentrator cathode achieves a rapid simultaneous degradation of EDTA and recovery of copper. The amount of degradation of EDTA was 99.9% while recovery of copper was 98.8% after 9 hours.