Highly efficient catalysis of chalcopyrite with surface bonded ferrous species for activation of peroxymonosulfate toward degradation of bisphenol A: A mechanism study

Abstract

Chalcopyrite nanoparticles (CuFeS₂ NPs) with abundant surface bonded ferrous were successfully prepared, characterized and used as a catalyst for peroxymonosulfate (PMS) activation and BPA degradation. The effect of reaction parameters such as initial pH, catalyst load, PMS concentration, initial BPA concentration and reaction temperature on BPA degradation in CuFeS₂-PMS system was systematically investigated. As a bimetallic sulfide, CuFeS₂ exhibits ultra-high activity for PMS activation compared with Cu₂S, FeS₂, CuFeO₂ and Co₃O₄. It was found that by co-use of 0.1 g L^-1 CuFeS₂ and 0.3 mmol L^-1 PMS, 20 mg L^-1 of BPA was almost completely degraded (99.7%) and reached a mineralization rate of 75% within 20 min. The highly catalytic activity of CuFeS₂ is closely related to two aspects: one is that S^2- in the catalysts promotes the cycling of Fe³⁺/Fe²⁺ and Cu²⁺/Cu⁺ cycles on the surface, and the other is the synergistic effect of Fe³⁺/Fe²⁺ and Cu²⁺/Cu⁺ cycles in the PMS activation. These interesting findings shed some new insight on the development of metal sulfides for the oxidative treatment of organic contaminants.

Keywords: Bisphenol A; Catalytic degradation; Chalcopyrite; Peroxymonosulfate; Sulfur.