Importance of Chloride Addition on Arsenite Removal by Aluminium Electrocoagulation

Abstract

Effect of chloride addition on arsenite removal by electrocoagulation process was carried out in this study. Electrocoagulation experiments were executed in a 5 L capacity rectangular tank equipped with 7 anodes and 7 cathodes. Addition of chloride significantly enhanced the arsenite removal efficiency of electrocoagulation process and the removal is purely by the separation process, rather than the oxidation of arsenite to arsenate by electrolytically generated active chlorine. 250 mg L−1 of chloride was found as optimal, and more than 99 % of arsenite were removed from its initial concentration of 1 mg L−1 at pH 6, applied voltage of 5 V, and 60 min of electrolysis. Sludge produced after electrocoagulation treatment was analyzed by scanning electron microscopy (SEM) / energy dispersive X‐ray analysis (EDAX), X‐ray diffraction (XRD), and Fourier transforms infrared (FTIR) techniques.