Simultaneous removal of lead, chromium and cadmium from synthetic water by electrocoagulation: Optimization through response surface methodology

Abstract

Present research was conducted to remove lead, chromium and cadmium simultaneously from synthetic water by electrocoagulation (EC) process using iron electrodes. Process parameters such as initial pH, current density, and treatment time were optimized using Box- Behnken design (BBD) of Response Surface Methodology (RSM). A high R2 value of Analysis of variance ensuring a satisfactory adjustment of the second-order regression model with the experimental data. Under the optimum conditions of initial pH: 5, current density: 140 A/m2, treatment time: 40 min the removal of lead, chromium, and cadmium were obtained as 99.9 %, 94.3 %, and 99.9 %, respectively. Results confirmed the validity of the EC process optimization and the adequacy of the model. Furthermore, the lead and cadmium concentration in treated water is also found below the level set by the CPCB for Indian effluent discharge.