TiO2薄膜气相光催化氧化低浓度三氯甲烷和三氯乙烯的研究

自行设计了气固相光催化实验系统,以铝材为担载体,TCM和TCE为模拟污染物,在常温、常压下,对辐射光源、气体相对湿度、污染物反应浓度等因素对TCM和TCE的光催化降解反应的影响进行了研究.结果表明,在研究所采用的实验条件下,辐射光源采用254 nm时的降解效率要比采用365 nm时高10%左右;气体相对湿度为40%时光催化降解效率最高;随着污染物反应浓度的增加,TCM的降解效率降低,而TCE的降解效率增加.初步的反应动力学研究结果表明,TCM和TCE在二氧化钛表面的光催化降解反应可采用Langmuir-Hinshelwood动力学方程来表征.

Photocatalytic oxidation of TCE and TCM over thin films of TiO2

The gas-solid phase photocatalytic experiment system was designed, aluminum sheet was selected as the supportive substrate and the influencing factors, such as the illumination source, the relative humidity (RH) and the concentration of the pollutants on the photocatalytic degradation reaction were studied with trichloromethane (TCM) and trichlorethylen (TCE) selected as the simulated pollutants under the normal pressure and temperature. The experiment results indicated that the degradation efficiency is 10% higher with 254 nm ultra violate than with 365 nm, and the degradation efficiency reaches the highest when the relative humidity is about 40%, with the increase of the concentration, the degradation of TCM is decreased, on the contrary, the degradation of TCE is increased. Preliminary kinetic studies of photocatalytic oxidation of TCM and TCE suggest that the reaction can be best described using the Langmuir-Hinshelwood kinetic equation.