Response surface methodology for the optimization of the electrochemical degradation of phenol on Pb/PbO2 electrode.
Résumé
he electrochemical oxidation of phenol on Pb/PbO2 electrode was carried out in order to develop a predictive model. A central composite design (CCD) was employed for the screening of significant operating parameters and to identify their most relevant interactions. The model equation obtained led to a classification of these parameters based on their level of significance, namely the current density, the temperature, the initial phenol concentration, and the agitation speed. In addition, three relevant interactions were found, current density--temperature, initial phenol concentration--current density and initial phenol concentration--temperature. After performing a screening of the various factors, response surface analysis led to the following optimal conditions for the yield of phenol degradation: 189 ≤ [pOH]0 ≤ 200 mg L−1, 19.66 ≤ i ≤ 25 mA cm−2, 600 rpm, and 60°C for the initial phenol concentration, the current density, the agitation speed, and the temperature , respectively. Under these conditions, the obtained phenol degradation yield was 71% and the chemical oxygen demand (COD) was reduced more than 45%.