WO_3-TiO_2/ZSM-5催化剂的制备及其光催化脱氯性能

采用浸渍法以钛酸丁酯和偏钨酸铵为原料制备了WO_3-TiO_2/ZSM-5光催化剂,并将其用于模拟柴油脱氯,利用XRD、N_2吸附-脱附、UV-Vis等技术对制备的催化剂进行表征,考察了WO_3-TiO_2/ZSM-5催化剂脱氯实验的最佳反应条件,研究了催化剂对不同有机氯化物配制的模拟油的脱氯实验。表征结果显示,WO3-Ti O2/ZSM-5光催化剂保留了ZSM-5分子筛的结构。实验结果表明,在WO_3和Ti O_2负载量分别为2.5%(w)和20%(w),催化剂焙烧温度550℃,脱氯实验的反应温度50℃,紫外灯光照时间为4 h,剂油体积比为1∶40时,WO3-Ti O2/ZSM-5光催化剂的脱氯率最高,达98.7%;WO_3-Ti O_2/ZSM-5催化剂对不同种类的有机氯化物脱除效果不同,脱除率最好的为CH_2Cl_2。催化剂经五次使用后仍有较好的脱氯效果。

Preparation of WO_3-TiO_2/ZSM-5 catalyst and photocatalytic dechlorination performance

WO3-TiO2/ZSM-5 photocatalyst was prepared by an impregnation method using butyl titanate and ammonium metatungstate as raw materials and was used in the simulation of diesel oil dechlorination. The catalysts were characterized by XRD,N2 adsorption-desorptionand,and UV-Vis,the optimal reaction conditions for the dechlorination experiments over WO3-TiO2/ZSM-5 catalysts were investigated and the dechlorination experiments of the simulated oils prepared by different organic chlorides using the catalysts were studied.The characterization results show that the structure of the ZSM-5 zeolite is retained. The experimental results show that the WO3-TiO2/ZSM-5 photocatalyst has the highest dechlorination rate of 98.7% when the loading of WO3 and TiO2 is 2.5%(w) and 20%(w) respectively,the calcination temperature of the catalyst is 550 ℃,the reaction temperature of dechlorination experiment is 50 ℃,the UV illumination time is 4 h,and the ratio of catalyst to oil is 1∶40;WO3-TiO2/ZSM-5 catalyst has different effects on the removal of different kinds of organic chlorides,and the removal rate on CH2Cl2 is the best. The catalyst still has good dechlorination effect after repetitive use for five times.