Simultaneous Denitrification and Decarbonization of Wastewater over In Situ Generation of ·ClO Radicals Through a Fast, High-Performance Electro-Filtration Process

The contamination of wastewater with organic pollutants and nitrogen compounds poses significant environmental challenges. The primary objective of wastewater treatment is the simultaneous denitrification and decarbonization of ammonia nitrogen into harmless by-products. This study presents a novel method for the directional generation of chlorine radical species like ·ClO and ·Cl using electro-reactive membranes (EMs), which were fabricated using an electro-deposition coupled template approach known as RuO₂@PbO₂-M. This method facilitates the rapid and efficient conversion of ammonia to nitrogen and concurrently reduces the chemical oxygen demand in the effluent. Our system achieved ultra-efficient simultaneous denitrification and decarbonization with minimal energy consumption in single-filtration mode, thereby eliminating the need for chemical precursors. We elucidate the formation pathway of ·ClO and ·Cl during the electrochemical oxidation process involving RuO₂@PbO₂-M, where ·Cl generated from RuO₂ reacts with ·OH from PbO₂ under hypochlorous acid conditions, thereby enhancing nitrogen and carbon removal. These findings highlight a novel filtration model that utilizes single-channel electro-filtration and an innovative reactive membrane design for ·ClO synthesis, which provides a new research framework for the concurrent removal of nitrogen and carbon, and offers a promising solution to enhance wastewater treatment efficiency.