Abstract

In this study, the efficiency of photo-oxidation (P) and electro-oxidation (E) processes were examined, combined and separately, in amoxicillin (AMX) removal in a modified reactor in which a granular activated carbon bed was used as an electrode in the E process. Moreover, the effects of time, electrolyte concentration, and current density on AMX removal efficiency were investigated using Design-Expert software and Box-Behnken design to determine optimum conditions for removing the contaminant. Then, the effect of concentration and pH variables on the removal efficiency was investigated. After determining the optimal conditions for all variables, chemical oxygen demand (COD) removal efficiency and finally the toxicity of the effluent from the combined photoelectron oxidation reactor (PE) were also investigated. The results showed that in order to achieve the efficiency of about 98, the optimum conditions for electrolyte concentration, time, and current density variables were 950 mg/L, 10 min, and 40 mA/cm(2), respectively. Furthermore, the removal efficiency of AMX increased by decreasing pH and contaminant concentration. The analysis of the effluent from the reactor in terms of toxicity showed that the toxicity reduced. Using granular activated carbon as a porous electrode increases the efficiency of the PE process, which, by removal of 98 AMX and 64 COD, provides good performance in reducing the toxicity properties of effluent.