Reduction performance and degradation mechanism of chlorinated hydrocarbon electrocatalytic hydrodechlorination using synthetic Ti/ Pd cathode

In this research, an orthogonal experiment (45) was conducted to explore the degradation of CT in Ti/Pd sealed cathode chamber, and electrochemical characteristics of electrodes were analyzed simultaneously, demonstrating its superior capability for the dechlorination of aqueous CT. The results showed there existed a suitable electrolytic condition for CT hydrodechlorination, when Na2SO4 concentration was 0.4 mg center dot L 1, current density was 12 mA center dot cm 2 and initial pH was 7 within 45 min electrolysis time, the 89.42 % of CT was degraded, and the complete vanishment of CT until 65 min occurred. SEM and EDS analysis were used to comprehensively characterize the Ti/Pd cathode. Besides, theoretical calculations showed that Pd modified cathode possesses excellent intrinsic catalytic activity. CV curves and K-L calculation elucidated the one-electron-transfer process underlying the stepwise dechlorination of chlorinated alkanes at the Ti/Pd electrode. Cl index calculations verified that CT degradation was partial dechlorination. The scavenging activity test of atomic hydrogen (H*ads) proved the pivotal roles of H*ads in CT hydrodechlorination. The voltage control degradation pathway of CT was put forward, which aligned well with the kinetic model. Overall, the Ti/Pd cathode represents a promising electrode material with significant potential for CT degradation from aqueous solutions.