Parametric and multiple response optimization for the electrochemical treatment of textile printing dye-bath effluent

Abstract

In this study, treatment of textile printing dye-bath effluent (DBE) has been performed by electro-coagulation (EC) method using aluminum (Al) electrode in a batch mode. Various operating parameters such as initial pH (pHo), current density (J), electrolysis time (t) and inter electrode distance (d) were varied so as to see their effect on multiple responses namely chemical oxygen demand (COD) removal (Y1), color removal (Y2) and specific energy consumed (kWh/kg of COD removed; Y3). Full factorial central composite design (CCD) has been used for carrying out experiments and optimizing responses Y1, Y2 and Y3. Multi-response optimization with desirability function approach has been used to simultaneously maximize Y1 and Y2, and minimize Y3. Optimized values of various responses were: Y1=94%, Y2=99.7% and Y3=0.011kWh/kg of COD removed. Scum and sludge generated during EC of DBE have also been analyzed for the possibility of their disposal.