MWNTs/TiO_2对典型氯苯类化合物的光催化降解研究

Study on photocatalytic degradation of typical chlorobenzenes with MWNTs/TiO_2

研究复合光催化剂MWNTs/TiO2对典型氯苯类有机化合物光催化降解动力学及主要光降解路径.结果表明,同一初始浓度和相同光催化降解实验条件下,60min时典型氯苯类有机化合物的光降解率均达到90%以上.其中六氯苯和五氯苯的光催化降解速率常数分别为0.0664h-1和0.0670h-1,其大小明显高于其它氯苯类化合物.1,二氯苯的光催化降解反应速率常数仅为0.0430h4--1,在典型氯苯类化合物中最小.三氯苯的3种同分异构体——1,3-三氯苯、24-三氯苯和1,5-三氯苯的光催化降解速率常数分别为0.0547h2,1,,3,-1、0445h0.-1和0.0439h-1.六氯苯的主要光催化降解路径为:HCB→PeCB→1,2,3,5-TeCB→1,2,4-TCB→1,4-DCB.

The photodegradation kinetics and the main photodegradation process of typical chlorobenzene compounds by Multi -walled Carbon Nanotubes coated with titanium dioxide （ MWNTs/TiO2 ） were investigated. The results showed that the photodegradation rate of the typical chlorobenzene compounds could achieve 90% at 60 min with the same initial concentration and experimental conditions of photodegradation. The photodegradation rate constants of hexachlorobenzene （ HCB ） and pentachlorobenzene （PeCB） were 0. 0664 h - 1 and 0. 0670 h - 1 , respectively, which were significantly higher than that of the other chlorobenzene compounds. However, the photodegradation rate constant of 1,4-dichlorobenzene （DCB） was only O. 0430 h- J , which was the lowest within all the typical chlorobenzene compounds. The photodegradation rate constants of the three isomers of trichlorobenzene （TCB） were