Flow-through electrochemical removal of benzotriazole by electroactive ceramic membrane

Benzotriazole (BTA) is a widely used anticorrosive additive that is of endurance, bioaccumulation and toxicity, and BTA industrial wastewater treatment remains a challenge. This study reports efficient electrochemical removal of BTA by titanium oxide (TiSO) electroactive ceramic membrane (ECM), indicated by 98.1% removal at current density of 20 mA.cm(-2 )and permeate flux of 692 LHM under cathode-to-anode flow pattern (1 h). Electrochemical analysis demonstrated the pH-dependent formation of anti-corrosive BTA film on the TiSO anode, which was responsible for improved BTA removal for cathode-to-anode (CA) flow pattern compared with that for anode-to-cathode (AC). The modelling results showed the CA flow pattern to be more favourable for BTA oxidation mediated by electro-generated center dot & nbsp;OH by preventing the formation of deactivation film via creating an alkaline boundary layer at the anode/electrolyte interface. Intermediates and essential active sites were identified by using experimental analysis and theoretical density functional theory (DFT) calculations, thereby the most likely degradation pathways were underlined. Toxicity analysis revealed remarkable decrease in oral rat LD50 values and bioaccumulation factor during electrochemical degradation of BTA. This study provides a proof in-concept demonstration of effective removal for anti-corrosive emerging pollutants by TiSO-ECM under flow through pattern.

Automated summary

This study reports efficient electrochemical removal of benzotriazole (BTA) using a titanium oxide (TiSO) electroactive ceramic membrane (ECM). The formation of an anti-corrosive BTA film on the TiSO anode was found to enhance the BTA removal. The results of experimental analysis and theoretical calculations identified the degradation pathways and showed a remarkable decrease in toxicity and bioaccumulation factor.