Abstract:
In order to improve the catalytic efficiency of the heterogeneous Fenton catalysts, the heterogeneous Fenton catalysts of Mo-doped FeS
2 (FeS
2@Mo) were synthesized by solvothermal method for the catalytic degradation of bisphenol A (BPA) in water. The morphology and structural composition of the catalysts were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD). And the effects of H
2O
2 concentration, FeS
2@Mo dosage, and initial pH value on BPA degradation efficiency were studied. The results showed that the Mo-doped FeS
2 presented petal-shaped spheroids with a size of 200-500 nm. The degradation effect is optimal at 5 mM H
2O
2, 100 mg/L FeS
2@Mo, and pH=3.5, and the degradation rate of BPA within 10 min reach 99.1%. Quenching experiments and electron paramagnetic resonance (EPR) tests confirmed the major active components of the system, included hydroxyl radicals(·OH), singlet oxygen(
1O
2) and superoxide radicals(·O
2-), and ·OH and
1O
2 were dominance. By measuring the concentration changes of Fe
3%2B and Fe
2%2B in the two reaction systems of FeS
2 and FeS2@Mo, it was found that the doping of Mo increased the ratio of Fe
2%2B in the solution, which promoted the conversion of Fe
3%2B to Fe
2%2B, improving the catalytic efficiency of Fenton.