Flow-through heterogeneous electro-Fenton system based on the absorbent cotton derived bulk electrode for refractory organic pollutants treatment

Abstract

The electro-Fenton reaction is traditionally carried out in a batch or flow-by reactor. However, the electro-Fenton performance is restricted by low utilization efficiency of catalysts, limited contact time of reactants, and the slow mass transfer. In this work, a flow-through heterogeneous electro-Fenton reactor was designed by using absorbent cotton derived three-dimensional carbon fiber network with iron oxide nanoparticles loaded as cathode. This flow-through electro-Fenton system can electrochemically catalyze O2 molecule to produce ·OH. During the continuous test, the phenol degradation and mineralization efficiency achieved 92.7% and 65.1%, respectively, demonstrating the efficient and stable performance toward pollutant elimination of flow-through electro-Fenton system. Moreover, the flow-through system was demonstrated to be effective in the pH range of 5 ~ 9, and powerful for various refractory organic pollutants degradation including sulfamethoxazole, atrazine and benzoic acid. The high heterogeneous electro-Fenton activity was mainly attributed to the continuous in-situ ·OH generation. This study offers a facile method to construct flow-through heterogeneous electro-Fenton device, which provides a promising technology for wastewater treatment with low cost, high performance and good stability.