Highly-efficient removal of Rhodamine B using a flow-through electrocatalytic filtration system: Characteristics, efficiency and mechanism.

• An electrocatalytic filtration system by a Ti/SnO 2 -Sb membrane anode was developted. • Effects of various operating parameters for RhB degradation were optimized. • Degradation mechanism of RhB in the electrocatalytic filtration system was proposed. • Electrocatalytic filtration system can efficiently eliminate RhB from wastewater. The objective of this research is to develop an effective electrocatalytic filtration system using Ti/SnO 2 -Sb membrane anodes for eliminating Rhodamine B (RhB) from wasteater. Compared to Ti/SnO 2 -Sb plate anode, the prepared Ti/SnO 2 -Sb membrane anodes featured smaller particle size, bigger electrocatalytic active surface area, lower charge transfer resistance, and higher potential for oxygen evolution. The electrocatalytic filtration system obtained RhB removal of 90.29% with EE/O of 5.51 kWh m−3 after 90 min of electrolysis when initial pH value was 5, current density was 10 mA cm−2, initial RhB concentration was 50 mg L−1, and membrane flux was 2.17 m3 (m2·h)−1, respectively. The flow-through electrocatalytic filtration system was found to be limited by kinetics under a high membrane flux and dominated by an indirect radical oxidation. Finally, the possible RhB degradation pathways were proposed based on the detected intermediates and density functional theory calculations. [ABSTRACT FROM AUTHOR]