Characterization of Cu-SBA-15 molecular sieve and its catalytic performance for oxidation of 4-nitrophenol in aqueous solutions

Cu-SBA-15 mesoporous molecular sieve was synthesized by the two-step hydrothermal crystallization method, and was characterized by XRD, N ₂ adsorption, FT-IR, TEM and UV-vis technologies, respectively. The results indicate that Cu-SBA-15 molecular sieve shows high ordered mesoporous structure with uniform pore size distribution. Some cupric ions could enter into the framework of SBA-15 molecular sieve, and connect with oxygen atoms on skeletal Si-OH groups in the SBA-15 molecular sieve with the distorted octahedral environment, and dispers on the pore wall of SBA-15 molecular sieve. The influences of reaction conditions, including H ₂O ₂ initial concentration, dosage of catalyst used and reaction temperature, on 4-nitrophenol removal rate were studied. Under the conditions of 4-nitrophenol initial concentration of 200 mg·L ^-1, H ₂O ₂ concentration of 1.2 g·L ^-1, catalyst loading of 0.1 g·L ^-1, and after the treatment at 60°C for 100 min, the 4-nitrophenol removal ratio could reach to 100% and TOC removal ratio could reach to 82.4%.