Comparative study of As (III) removal efficiency from water by electrocoagulation and conventional coagulation [articol]

Abstract

The purpose of this paper was As (III) removal from simulated water by electrocoagulation (EC). The working conditions were: pH = 7, As (III) concentration 100 μg/L, and 0.01 M NaCl as supporting electrolyte. The sacrificial anode was made of aluminium and applied current densities were 25, 50 and 150 A/m2 at various electrolysis times. The results of EC were compared with those obtained by conventional coagulation (CC). The coagulation reagent was AlK(SO4)2.12H2O at the same concentration of Al3+ in solution as in EC experiments and working conditions: solutions of 100 μg/L As (III) and pH = 7. By comparison, As (III) was practically removed from solutin by EC, while arsenic residual concentration was 63.08 mg/L for 604 mg/L of alum by CC.