Mos2 Co-Catalysis Promoted Cao2 Fenton-Like Process: Performance And Mechanism

Fenton reaction is widely applied to treat organic contaminant through hydroxyl radicals (HO center dot), which is formed from the catalytic reaction of hydrogen peroxide (H2O2) and Fe2+. Nevertheless, its well application for actual wastewater has been confined by the narrow range of pH, disproportionation of H2O2 and inefficiency of Fe2+/ Fe3+ circulation. To overcome these shortcomings, an improved Fenton-like method applying calcium peroxide (CaO2) as the substitution of H2O2 and molybdenum disulfide (MoS2) as the co-catalyst was proposed. The results indicated the efficient rhodamine B (RhB) removal (98.6%) was achieved under the conditions of 1 mmol L-1 CaO2, 0.5 mmol L-1 Fe2+, 0.3 g L-1 MoS2, and initial pH 5.85 within 5 min, and this system could well degrade other dyes, antibiotic, and phenol. The MoS2 addition could promote the Fe2+/Fe3+ conversion and H2O2 disintegration. The radical masking tests and electron paramagnetic resonance demonstrated that the HO center dot was the main active substances during this process. The decomposition intermediates of RhB were identified through the mass spectra analysis, and their ecotoxicities were assessed by the toxicity estimation software. Finally, this process also presented a favorable performance for the real wastewater treatment, which is a potential route to promote the development of Fenton method.