Membrane Separation Coupled with Electrochemical Advanced Oxidation Processes for Organic Wastewater Treatment: A Short Review

Abstract

Research on the coupling of membrane separation (MS) and electrochemical advanced oxidation processes (EAOPs) has been a hot area in water pollution control for decades. This coupling aims to greatly improve water quality and focuses on the challenges in practical application to provide a promising solution to water shortage problems. This article provides a summary of the coupling configurations of MS and EAOPs, including two-stage and one-pot processes. The two-stage process is a combination of MS and EAOPs where one process acts as a pretreatment for the other. Membrane fouling is reduced when setting EAOPs before MS, while mass transfer is promoted when placing EAOPs after MS. A one-pot process is a kind of integration of two technologies. The anode or cathode of the EAOPs is fabricated from porous materials to function as a membrane electrode; thus, pollutants are concurrently separated and degraded. The advantages of enhanced mass transfer and the enlarged electroactive area suggest that this process has excellent performance at a low current input, leading to much lower energy consumption. The reported conclusions illustrate that the coupling of MS and EAOPs is highly applicable and may be widely employed in wastewater treatment in the future.

A review on ion-exchange nanofiber membranes: properties, structure and application in electrochemical (waste)water treatment

“…• The use of a membrane can avoid by-product formation and the reduction of the oxidized pollutants on the cathode surface [6,321]. • A high permeation flux and treatment efficiency is obtained by the presence of the membrane, while the fouling of the membrane is reduced due to the synergetic effect of the electrochemical process [325,326].…”

Review—Electrochemical Separation of Organic and Inorganic Contaminants in Wastewater

“…Several attempts to maintain high current efficiencies have been undertaken, including the incorporation of ion-exchange resin beads to battle the high potential drop in ED systems 51,181 and the introduction of reactive electrochemical membranes (REM) to increase mass transfer and thus reaction rates and current efficiency in wastewater treating electrochemical systems. [182][183][184] Other suggestions include careful selection and online monitoring and adjustment of the current applied based on the measured limiting current density for specific wastewater. 185 Moreover, other strategies are combining different electrochemical technologies for energetic support, e.g., a combination of MFC with ED, or as pre-treatment of the other to concentrate the wastewater stream with regards to the removal of the ion of interest.…”

“…185 Moreover, other strategies are combining different electrochemical technologies for energetic support, e.g., a combination of MFC with ED, or as pre-treatment of the other to concentrate the wastewater stream with regards to the removal of the ion of interest. 175,184 A striking advantage that electrochemical technologies serve for is selectivity. This is highly important within the context of industrial wastewater that often come with a high complexity but also contain valuable resources that could be selectively recovered.…”

Adsorptive Elimination of a Cationic Dye and a Hg (II)-Containing Antiseptic from Simulated Wastewater Using a Metal Organic Framework

“…Currently, there are different methods for the removal of these contaminants, such as osmosis [ 13 ], photocatalytic degradation [ 14 ], membrane filtration [ 15 ], electrochemical process [ 16 ], electrolysis [ 17 ], organic processes [ 18 ], and adsorption [ 19 , 20 ]. However, techniques other than adsorption are expensive, time-consuming, and complex, with poor recycling efficiency.…”