Direct oxygen transfer mediated controllable oxidation in electrochemical membranes facilitate eco-friendly removing DMSO from industrial wastewater

Dimethyl sulfoxide (DMSO), a prevalent organic solvent in industrial wastewater, poses challenges in conventional treatments such as Fenton oxidation or ozonation due to excessive chemical-energy consumption and uncontrolled carbon emissions. Herein, we introduce an electrocatalytic chlorine-mediated direct oxygen transfer pathway, enabling controllable oxidation of DMSO into the more biodegradable and less toxic dimethyl sulfone (DMSO 2 ). We found that the electrocatalytic membrane modified with multi-Sn/Sb sites possess a desirable activity for chlorine evolution reaction, which could generate a high steady-state concentration (1.73× 10 −13 M) of ClO• radicals. DFT calculations reveal that ClO• radicals more readily engage with DMSO via sulfur-oxygen bridging, rapidly forming DMSO 2 through chlorine-oxygen bond cleavage. Under these circumstances, the electrocatalytic membrane achieves near-complete DMSO (100   mg   L −1 ) removal at 10   min, with an energy consumption of only 0.20 kWh m −3 . Moreover, the system implements controllable oxidation of DMSO, reaching up to 88.6% conversion to DMSO 2 at a flux of 800   L   m⁻ 2 h⁻ 1 , while generating only 0.26 kg-CO 2 m ⁻3 of greenhouse gas emissions - significantly lower than those from Fenton and PMS activation processes. These findings highlight the promise of direct oxygen transfer mediated controllable oxidation as a sustainable and eco-friendly strategy for organic wastewater purification.