Copper (II) removal in a column reactor using electrocoagulation: Parametric optimization by RSM using central composite design.

In the present work, electrocoagulation was applied for copper removal from aqueous solution employing iron electrodes in a cylindrical reactor. A four-factorial central composite design (CCD) based on response surface methodology (RSM) was applied to study the effect of various process parameters on removal efficiency and energy consumption as the responses. On optimization, maximum removal efficiency up to 95 %was attained with energy consumption as 0.903 W- hour per gram removal of Cu (II) at applied current 0.26 A, initial copper concentration of 27.8 ppm, application time of 5.4 minutes and pH 7. The interaction between the process variables was evaluated by using the obtained 3-D plots. The models generated were validated by analysis of variance (ANOVA). Studies carried on Cu (II) removal rate showed adsorption suited pseudo-I(st) order kinetics best. Overall the electrocoagulation process proved efficient, low cost and a promising alternative to conventional treatment procedures in removing Cu (II).