In the present work, the treatment of PTA (purified terephthalic acid) for synthetic and actual waste water was executed by electrochemical (EC) technique using stainless steel (SS) as electrode material in a batch reactor. A fully factorial central composite design (CCD) with four different parameters specifically P-H: 3.60-10.40, current density (A/m(2)): 31.25-156.25, reaction time (min): 30-250, inter-electrode distance (cm): 0.5-2.5, all these parameters at five different levels were performed to optimize the aspect for higher % COD removal. The optimum % COD removal (pH - 8.2, time 180 min, C.D. 125 A/m2 and inter electrode distance I cm) was 70.86% for synthetic and 66.72% for actual waste water as a set of 30 runs were performed for both the type of waste waters. (C) 2014 Elsevier B.V. All rights reserved.