土壤中TNT的TiO_2光催化降解动力学研究  

TiO_2 photocatalytic degradation kinetics of TNT in soil

作　　者：张文通[1] 陈勇[1] 薛明[1] 谷科成[1] 

机构地区：[1]后勤工程学院国防建筑规划与环境工程系,重庆401311

出　　处：《环境化学》2016年第4期826-832,共7页Environmental Chemistry

基　　金：重庆市自然科学基金(CSTC;2008BB7139)资助~~

摘　　要：为了高效修复受TNT污染的军事训练场地土壤,利用纳米TiO_2光催化降解土壤中的TNT污染物,并采用高效液相色谱法测定降解后剩余的TNT含量.研究了光催化降解TNT的影响因素(如初始TNT浓度、p H、TiO_2用量、土层厚度等)及其动力学规律.研究结果表明,加入TiO_2催化剂后能将土壤中浓度为500 mg·kg-1的TNT的去除率从36%显著提高到95%以上;另外,在土层厚度<8mm、TiO_2用量为0.5wt%—3wt%的条件下,TNT的光催化降解符合拟一级动力学规律,且可用L-H模型描述;当催化剂用量为0.1wt%时,此时为零级反应.通过正交实验可知土层厚度大小对TNT的光催化降解影响最大.In order to repair military training ground soil polluted by TNT efficiently,nanometer TiO2 was used in the photocatalytic degradation of TNT in the soil. High-performance liquid chromatography（ HPLC） was used to analyze the content of TNT after the degradation. TNT degradation factors（ such as initial concentration of TNT,initial pH,dosage of TiO2,soil thickness and so on） and degradation kinetics were investigated. The results show that,addition of TiO2 catalyst to the soil increased the degradation rate of TNT from 36% to more than 95% when the initial concentration was 500 mg·kg^-1. Moreover,when the depth of soil was less than 8 mm and the amount of TiO2 was 0. 5wt% —3wt%,the photocatalytic degradation of TNT is in accord with the pseudo-first order kinetics law,and can also be described by the L-H dynamic model. When the usage of the catalyst is 0. 1 wt%,it＇s a zero order reaction. After the orthogonal experiments,it was found that soil thickness influenced the degradation of TNT most significantly.

关 键 词：TNT 土壤 TIO2 光催化 动力学 

分 类 号：X131.3[环境科学与工程—环境科学]