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利用溶胶-凝胶法在改性的ZSM-5分子筛上负载TiO_2制备复合光催化剂TiO_2/ZSM-5m,采用扫描电镜、N2吸附-脱附等温线和X射线衍射对材料进行表征。通过耦合Fe~(2+)/S_2O_8~(2-)产硫酸根自由基SO_4~-·体系,以对硝基苯酚(pNP)为目标污染物,系统考察了初始pH、TiO_2/ZSM-5m投加量、FeSO_4、Na_2S_2O_8浓度和初始浓度对pNP降解性能的影响。结果表明,在TiO_2/ZSM-5_m投加量为0.8g/L,pH为4.0,FeSO_4为0.4g/L,Na_2S_2O_8为2.4g/L,常温下反应240min的优化条件下,对pNP(初始浓度50mg/L)去除率达到99.31%,光催化降解动力学符合Langmuir-Hinshelwood模型,UV-vis图谱推测对硝基苯酚分子结构发生改变,被有效降解。
The composite photocatalyst TiO_2 / ZSM-5m was prepared by sol-gel method on modified ZSM-5 zeolite. The materials were characterized by scanning electron microscopy, N2 adsorption-desorption isotherm and X-ray diffraction. The initial pH, the molar ratio of TiO_2 / ZSM-5m to p-nitrophenol (pNP) as the target pollutant were determined by coupling the SO_4 ~ (superscript 2 +) system with Fe 2 + / S_2O_8 ~ (2-) Effect of dosage, FeSO 4, Na 2 S 2 O 8 concentration and initial concentration on pNP degradation. The results showed that under the optimized conditions of dosage of TiO_2 / ZSM-5_m 0.8g / L, pH 4.0, FeSO_4 0.4g / L, Na_2S_2O_8 2.4g / L and 240min reaction at room temperature, 50mg / L) removal efficiency reached 99.31%. The kinetics of photocatalytic degradation accorded with the Langmuir-Hinshelwood model. The UV-vis spectra suggested that the molecular structure of p-nitrophenol changed and was effectively degraded.