Synergetic Effects Of Bioelectrochemistry and Cuco2s4 Addition on Activation of Peroxymonsulfate And Catalyst Regeneration In a Bioelectrochemical System

Abstract

Bielectrochemical methods have been used to induce peroxymonosulfate (PMS) activation for removing contaminants, yet low PMS activation rate limited its reaction activity. In this study, a bioelectrochemical system with CuCo2S4 as cathode catalyst for PMS activation (PMS/CuCo2S4-BEC) was established. The results showed that three-dimensional nanoflake structure of CuCo2S4 could provide more active sites for PMS activation and exhibited the excellent electrochemical performance. The apparent degradation rate (ka) of Rhodamine B(RhB) in this system was 6.5 times and 1.2 times higher than that of without CuCo2S4 and without bioelectrochemisty respectively, suggesting that PMS activation was attributed to both CuCo2S4 and bioelectrochemisty in the system. In addition, the catalytic decay of CuCo2S4 under closed-circuit condition was approximately 3 times slower than that of open-circuit condition, indicating that the stability of CuCo2S4 was increased significantly. This is mainly attributed to the in-situ regeneration of Cu2+ and Co3+ through receiving the electrons generated from bioelectrochemical anode. The radical quenching results indicated that RhB were degraded mainly through the radical pathway, in which sulfate radical was the key active species. This study provides an energy-saving approach for PMS activation, which will be useful for further development of PMS-based advanced oxidation process.

Keywords: PMS activation, Synergetic effects, CuCo2S4, Catalyst regeneration, bioelectrochemical system