(2022) Journal of the Taiwan Institute of Chemical Engineers_3D hexagonal hierachitectured cobalt sulfide as an enhanced catalyst for activating monopersulfate to degrade sunscreen agent ensulizole

Liu W.-J., Kwon E., Thanh B.X., Khiem T.C., Lisak G., Lee J., Lin K.-Y.A.

(Taiwan Institute of Chemical Engineers) Journal of the Taiwan Institute of Chemical Engineers ISSN: 18761070 Vol.131 Issue. Article No.104109 DOI: 10.1016/j.jtice.2021.10.009

As ensulizole (ESL) is a widely-used UV absorber, release of soluble ESL into the aquatic environment would pose risks to the ecology because ESL is an endocrine disrupting compound. For establishing efficient processes to eliminate ESL from water, sulfate radical (SR)-based advanced oxidation processes are preferable owing to stronger oxidation potential of SR. Recently, cobalt sulfides (CoS) have drawn growing attention as CoS is validated to possess more active redox characteristics, making CoS a more powerful catalyst for activation monopersulfate (MPS) to generate SR. Since structures of catalysts determine their catalytic activities, a unique hexagonal hierarchitectured CoS (HHCS) is developed here through a simple one-step hydrothermal reaction to consist of a 3D hexagonal particle embedded with nanosheets interwoven for serving as a heterogeneous catalyst to activate MPS for degrading ESL. With HHCS = 100 mg/L and MPS = 300 mg/L, 5 mg/L of ESL is completely eliminated in 60 min, and HHCS surpassingly outperforms Co₃O₄ for degrading ESL. Ea of ESL degradation by HHCS+MPS is also determined as a relatively low value of 48.2 kJ/mol. The activation mechanism/degradation pathway of ESL degradation by HHCS + MPS is investigated to understand degradation behaviors for developing SR-based processes of ESL degradation using CoS catalysts. © 2021 Taiwan Institute of Chemical Engineers