• 关键词：2,4-二氯酚  光催化  降解  机理  动力学

• 基金项目：

• 孙振世
• 浙江大学环境工程系,杭州 310029

• 杨晔
• 浙江工业大学环境工程系,杭州 310032

• 陈英旭
• 浙江大学环境工程系,杭州 310029

• 朱松
• 浙江大学环境工程系,杭州 310029

• 摘要：以主波长为365nm的紫外光灯为光源,纳米TiO₂薄膜为光催化剂,研究了2,4-二氯酚光催化降解的产物及Cl^-对2,4-二氯酚光催化反应动力学的影响,并进一步探讨了Cl^-对2,4-二氯酚光解影响的机理.2,4二氯酚可以经光催化氧化被彻底矿化,结合外加Cl^-对2,4-二氯酚光催化降解的影响和LH反应动力学分析,可以认为Cl^-对2,4-二氯酚光催化降解的抑制作用,是由于Cl^-与2,4-二氯酚在TiO₂表面竞争同一活性位点所致.因此,当光催化反应进行到Cl^-在TiO₂表面竞争性吸附较强时,在反应动力学方程中必须考虑Cl^-的竞争性作用.

• Abstract：Heterogeneous photocatalytic degradation of 2,4-dichlorophenol on TiO₂ film illuminated by a 2×6W ultraviolet lamp had been investigated.The rate of oxidation of 2,4-dichlorophenol decreased obviously with the addition of chlorides.The data were described in terms of salt effects,surface active sites having adsorption properties and by Langmuir-Hinshelwood equation.The model provided the best fit to the data by assuming that inorganic anions inhibited the degradation of 2,4-dichlorophenol through competing with the initial substrates for oxidizing sites on the surface of TiO₂.Therefore,the competition of chloride with 2,4-dichlorophenol must be involved in the kinetics of photocatalytic degradation of 2,4-dichlorophenol.

• Key words：dichlorophenol  photocatalysis  degradation  mechanism  kinetics

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