Electrochemical microfiltration treatment of bisphenol A wastewater using coal-based carbon membrane

Abstract

A novel electrochemical microfiltration process, in which the coal-based carbon membrane (CCM) serves as the membrane filter and anode simultaneously, was designed for the decontamination of bisphenol A (BPA) wastewater in this work. Effects of operational parameters, including residence time (RT), initial BPA concentration and electrical conductivity of aqueous solution, on the treatment performance were also investigated. Morphology and electrochemical properties of carbon membrane were analyzed by scanning electron microscope (SEM) and electrochemical workstation, respectively. As expected, the electrochemical microfiltration process demonstrated excellent BPA removal ability due to the synergistic effect between membrane filtration and electrochemical oxidation. Under the optimal conditions of applied voltage 2.0 V, initial BPA concentration 50 ppm, 0.1 mol/L Na2SO4 and residence time 0.88 min for the electrochemical microfiltration of CCM, the BPA and COD removal efficiency was up to nearly 97% and 90%, respectively, and the energy consumption was only 0.50 kWh kgCOD−1. During the treatment, the degradation of BPA was attributed to the combination of direct and indirect oxidation. And a possible degradation pathway of BPA was proposed based on the intermediates detected by high-performance liquid chromatography-mass spectrometry (HPLC-MS).