摘要
以水热法合成的PbMoO4微晶体为催化剂,考察了反应溶液pH、污染物初始浓度和催化剂用量对其光催化降解灭幼脲的影响,研究了光催化降解过程的反应动力学和作用机理。结果表明,最佳反应溶液pH 6.0,污染物初始质量浓度20mg/L,催化剂用量0.4g/L。反应4h灭幼脲降解率达99.96%,矿化率达66.4%,降解反应符合一级动力学。通过加入自由基清除剂时的对比实验发现PbMoO4微晶体主要通过空穴和.OH的氧化作用使灭幼脲降解,其中空穴起主要作用。
PbMoO4 microcrystals has been prepared through a hydrothermal process and used for the photocatalytic degradation of chlorbenzuron. Kinetics and mechanism of the degradation reaction were investigated. Experimental results indicated that the optimum condition were observed at the pH of 6.0, the initial mass concentration of 20 mg/L, and the catalyst of 0.4 g/L. In this condition, the degradation rate and the TOC removal could be reached to 99.96% and 66.4% respectively after 4 h irradiation. The reaction kinetics could be described by a first-order degradation. It was demonstrated by addition of scavenger that the valence band hole and hydroxyl radical played a significant part in the degradation of chlorbenzuron, in which the hole acted the dominant role.
基金
高等学校博士学科点专项科研基金资助项目(20100146110004)
