Application of the electrocoagulation in the plating wastewater treatment

Abstract

     This study used the electrocoagulation bench scale with six iron plates and cylinder reactors to evaluate the removal efficiency of total chromium and Cr (IV) in the plating wastewater. The optimal operating conditions were determined by RSM and Design-Expert 12 software, including the current density of 5 A/m², pH = 9, and 31- minute reaction time. Total Chromium and Cr (IV) treatment reached 92,18 ± 1,00% and 79,77 ± 1,35%, respectively, which were higher than the conventional coagulation-flocculation method using FeSO₄ (10%) with the efficiency of 90,44 ± 2,14% total Cr and 62,88 ± 1,54% Cr (IV). Additionally, the generated sludge in the electrocoagulation process was less than another, approximately ¾ of the conventional coagulation-flocculation process. Therefore, electrocoagulation may be applied in plating wastewater containing chromium treatment to reduce operating costs.