Experimental investigation of chemical oxygen demand, lignin and phenol removal from paper mill effluents using three-phase three-dimensional electrode reactor

The removal of chemical oxygen demand (COD), lignin and phenol from paper mill effluents was experimentally investigated using an electrode cell consisting of graphite electrode and powder-activated carbon (as working electrode). The effects of electrolyses time, voltage, initial pH, activated carbon (AC), NaCl amount and airflow were selected as parameters. The experimental results show that removal effi­ciency significantly depends on the applied cell voltage, airflow, time, salt amount and pH. For electrolyses under the conditions of 25.0V cell voltage, 5.0 min, in presence of air 2.0 minL-1, NaCl 5.0gL-1 at low pH and AC 20gL-1, it can be said that the removal of COD, lignin and phenol from the paper mill effluent were almost higher than 90%. The present study proves the effectiveness of electrochemical treatment for the highly concentrated organic pollutants present in paper mill effluents.