Degradation of bisphenol A by electrocatalytic wet air oxidation process: Kinetic modeling, degradation pathway and performance assessment

Abstract

Pharmaceuticals and personal care products (PPCPs) are becoming ubiquitous in environment, and effective removal of PPCPs from contaminated water bodies is urgently needed to avoid their potential hazards to human health. Electrocatalytic wet air oxidation (ECWAO) process is a highly efficient technology for the rapid and deep mineralization of PPCPs under room condition. In this work, the degradation behavior of the bisphenol A (BPA), a typical PPCP compounds, in the ECWAO process is comprehensively investigated. A simple kinetic model is developed to describe the removal rate of BPA as a response to the initial concentration of BPA and intensity of electric field. BPA removal in the ECWAO process is accompanied by its partial mineralization, with p-isopropenyl phenol, benzoquinone and propanedioic acid as intermediate products. At last, the performances of the ECWAO process in treating BPA and other two PPCP compounds, i.e. triclosan (TCS) and sulfamethoxazole (SMX), are assessed under a condition optimized by the kinetic model. The results demonstrate the ECWAO process is able to totally eliminate the toxicity of PPCPs-contaminated waters at low energy consumption. Notably, the treated-waters show good aerobic biodegradabilities, enabling such a process a prospective pretreatment for coupling with aerobic biological process.