Application of Response Surface Methodology for Optimization of Phenol Removal from a Simulated Wastewater Using Rotating Tubular Packed Bed Electrochemical Reactor

Phenol removal from simulated wastewater by indirect electrochemical oxidation was investigated using a rotating tubular packed bed electrochemical reactor. Effects of operating parameters like current density (3-15mA/cm(2)), rotation speed (100-500 rpm), initial phenol concentration (20-100ppm), and pH (3-9) were investigated. Optimization of the process parameters was carried out by adopting response surface methodology (RSM) combined with Box-Behnken Design (BBD) where COD removal efficiency (RE %) was selected as a response function. The results indicated that initial phenol concentration has the main effect on the COD removal efficiency followed by current density then pH and rotation speed. The results of regression analysis revealed that the experimental data could be fitted to a second-order polynomial model with a value of determination coefficient (R-2) equal to 98.38% .The optimum conditions of the process parameters based on RSM method were an initial phenol concentration of 41 ppm, current density of (9.3 mA/cm(2)), rotation speed of 367 rpm and pH = 3 where COD removal efficiency of (99.83%) was accomplished after 60 min of electrochemical oxidation process in which current efficiency of (9.87%) was observed and energy consumption of (179.86 KWh/Kg COD) was required.