Dark-degradation of reactive brilliant blue X-BR in aqueous solution using α-Fe₂O₃

The precursor of Fe₂O₃ was prepared by chemical precipitation method with sodium hydroxide (NaOH) and iron chloride hexahydrate (FeCl₃ · 6H₂O). The samples annealed at different temperature were characterized by means of X-ray diffraction (XRD) and infrared absorption spectroscopy (IR). Degradation of reactive dye in aqueous solution was used to evaluate the catalytic performance of the Fe₂O₃. The experiments of degradation had been done in dark place. The experimental results indicated that the catalytic property of the precursor of α-Fe₂O₃ was excellent. The mechanism of the degradation of reactive dye in aqueous solution was investigated by comparing the data in the absence and presence of oxygen. The precursor of α-Fe₂O₃ annealed at 300 °C was the best. The degradation rate of reactive brilliant blue X-BR could exceed 95% in 8 min at 25 °C when the concentration of the precursor of α-Fe₂O₃ was 0.1 g/L. The mechanism of the catalytic oxidation reaction was investigated by comparing the X-BR catalytic oxidation data in the absence and presence of oxygen.