摘要
以对氯苯甲酸钠为模型污染物 ,研究了不同光强条件下的光催化降解动力学 .结果表明对氯苯甲酸钠的光催化降解动力学可以用Langmuir Hinshelwood模式来描述 ,但其中的动力学参数与光强有关 .速率常数kr 随入射光强的升高而增加 ,而表观吸附常数Ks 却随入射光强的升高而降低 .kr 和K- 1s 近似与光强呈幂函数的关系 .说明提高光强虽然可以增加光催化降解速率但会降低其能量利用效率 。
Kinetics of photocatalytic degradation were investigated at different light intensities using para chlorobenzoate as a model pollutant. It was experimentally found that the Langmuir Hinshelwood model could satisfactorily describe all the kinetic processes. However, the two crucial parameters involved in the L H model were dependent of the incident light intensity. With elevated light intensity, the rate constant, k r, increased whereas the apparent adsorption constant, K s, decreased. Grossly, both k r and K -1 s were correlated with the light intensity in a power law. The experimental discovery implies that the photonic efficiency would be much deteriorated with increased radiation intensity although the reaction rate can be enhanced. Applying mild light intensity might be one of the critical strategies in photocatalytic reactor design to improve the photonic efficiency.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2001年第4期56-59,共4页
Environmental Science
基金
中日合作项目
关键词
光催化降解
动力学
光强
模式
对氯苯甲酸钠
废水处理
有机废水
photocatalytic degradation
kinetics
light intensity
Langmuir Hinshel model
para chlorobenzoate
