MnOOH/carbon-based reactive electrochemical membrane for aqueous organic pollutants decontamination.

Abstract

The electrochemical filtration process (ECFP), which integrates the benefits of membrane separation with electrochemical advanced oxidation, exhibits significant potential for water decontamination. A key aspect in realizing practical applications of ECFP lies in the development of cost-effective, high-performance reactive electrochemical membranes (REM). In this work, a novel carbon-based REM (MCM-30) was prepared by coating the low-cost coal-based carbon membrane (CM) with MnOOH nano-catalyst through a simple and environmentally friendly electrochemical deposition method. Results indicated that the nano-MnOOH catalyst significantly improved the hydrophilicity and electrochemical properties of the CM, thereby enhancing its permeability and removal efficiency towards bisphenol A (BPA). The effects of deposition time, applied voltages, flow rates, electrolyte concentrations, and water matrixes on BPA removal efficiency were systematically investigated. Under optimal conditions, 30 min deposition, 2.0 V applied voltage, 2 mL min^-1 flow rate, 0.1 mol L^-1 Na₂SO₄ electrolyte concentration, the BPA removal efficiency of the MCM-30 reached to over 95%, which is much higher than that of the CM. The improved water treatment performance of MCM-30 during the electrochemical filtration could be attributed to the enhancement in both direct and indirect oxidation owing to the nano MnOOH deposition. Furthermore, the MCM-30 is recyclable and can be applied across various water backgrounds and pollutant types.