三氯乙烯在薄膜催化剂上的光催化降解动力学

Photocatalytic degradation kinetics of trichloroethylene of low concentrations on film catalyst.

研究了不同初始浓度三氯乙烯(TCE)在TiO2薄膜催化剂上的光催化降解.结果表明,TCE在主波长为254nm的低压汞灯照射下易于发生光降解反应,而TiO2薄膜催化剂能显著提高TCE的降解.光催化降解反应的伪一级速率常数随初始浓度的增加先升后降.在Langmuir-Hinshelwood方程基础上建立的光催化降解动力学模型包含了发生在薄膜催化剂表面的光催化氧化过程和发生的溶液体相的光降解过程,该动力学模型适用于表达低浓度有机物在薄膜催化剂上的光催化降解动力学.

Kinetics of photocatalytic degradation of trichloroethylene (TCE) of different initial concentrations on TiO2 film catalyst was studied. TCE was photodegraded easily under irradiation of low pressure mercury lamp with main wave length of 254nm; and the catalyst could raise markedly the TCE degradation. The apparent velocity constant of photocatalytic degradation increased with the increase of initial concentration and then decreased. The photocatalytic degradation kinetic model established on the basis of Langmuir-Hinshelwood equation, embodied the photocatalytic oxidation occurred on film catalyst surface and the photodegradation of solution phase occurred. This mode could be used suitably to express the kinetics of photocatalytic degradation of catalyst of low concentration on the film.