Cu-SBA-15分子筛的表征及其催化氧化水溶液中4-硝基苯酚的性能

Characterization of Cu-SBA-15 Molecular Sieve and its Catalytic Performance for Oxidation of 4-Nitrophenol in Aqueous Solutions

采用两步水热晶化法合成了Cu-SBA-15介孔分子筛,并且用XRD、N2吸附、FT-IR、TEM以及UV-vis对所合成的样品进行了表征。结果表明,Cu-SBA-15具有高度有序的介孔结构和均一的孔径分布。部分铜离子进入了分子筛骨架,部分铜离子以八面体配位环境与骨架硅相连均匀分布在孔壁上。Cu-SBA-15(含铜6.0%)在催化氧化水溶液中4-硝基苯酚的反应中具有良好的催化活性,主要考察了H2O2初始浓度、催化剂用量、处理温度等因素对4-硝基苯酚氧化效果的影响。在4-硝基苯酚初始浓度为200 mg L 1、H2O2初始浓度为1.2 g L 1、在60℃的条件下处理100 min,4-硝基苯酚去除率达100%,TOC去除率可达82.4%。

Cu-SBA-15 mesoporous molecular sieve was synthesized by the two-step hydrothermal crystallization method, and was characterized by XRD, N2 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 H2O2 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, H2O2 concentration of 1.2 g.L^-1, catalyst loading of 0.1 g.L^-1, and after the treatment at 60℃ for 100 min, the 4-nitrophenol removal ratio could reach to 100% and TOC removal ratio could reach to 82.4%.