Insight into the synergy effect of BDD anode for peroxymonosulfate activation: The radical and non-radical mechanisms

Abstract

Background

The widespread use of carbamazepine (CBZ) has led to environmental contamination of water bodies, raising concerns about water quality safety and ecosystem health.

Methods

In this study, an electrochemical process for activating peroxymonosulfate is conducted, with boron-doped diamond as anode (E-BDD-PMS). The BDD anode possesses a high over-potential for oxygen, which effectively suppresses the generation of oxygen evolution side reactions.

Significant findings

Under the optimal condition, 89.57 % of CBZ could be removed within 40 min. The quenching experiments and EPR analysis revealed that both free radicals (•OH and ${\text{SO}}_4^{•-}$) and nonradicals (¹O₂) participated in the reaction. Specifically, the CBZ oxidation mainly occurs via four pathways: DET, PMS oxidation, radical oxidation, nonradical oxidation. The contributions of these four pathways are 11.67 %, 5.84 %, 32.72 % and 50.08 %, respectively. Meanwhile, the removal of seven different pollutants are also studied. Based on the experimental results, the E-BDD-PMS process has a great promise in organic contaminants degradation.