Optimization of COD Removal from Pharmaceutical Wastewater by Electrocoagulation process using Response Surface Methodology (RSM)

Abstract

In this research, the feasibility of using an electrocoagulation method as a process for treating of hospital wastewater generated from Al-Dewaniya hospital located at Al-Dewaniya city/Iraq was investigated. Batch experimental runs were conducted using an electrochemical reactor with stainless steel and aluminum as cathode and anode, respectively. The impact of operating variables like current density, pH, and addition of NaCl on the removal of chemical oxygen demand (COD) was investigated. For this purpose, Box-Behnken (BB) design based on the Response Surface Methodology (RSM) was adopted to design and analyze the results. The results revealed that the current density has the major impact on the efficiency of COD removal followed by addition of NaCl while pH has the lower effect on the COD removal under the studied range of pH. The optimized operating parameters were a current density of 25 mA/cm2, pH of 8.6,and NaCl addition of 2.06 g/l in which COD removal efficiency of 99.45% was achieved with a specific energy consumption of 26.079kWh/kgCOD.