介质阻挡放电-光催化降解甲苯的实验研究

Experimental Investigation of Toluene Degradation by Photocatalysis Coupled with Dielectric Barrier Discharge

采用介质阻挡放电(DBD)-光催化技术对甲苯气体进行处理.在不同的能量密度、气体流量、放电时间以及反应器结构(即内电极直径)条件下,考察了介质阻挡放电驱动光催化剂TiO2对甲苯转化率的影响.结果表明:添加TiO2能提高甲苯的转化率,并提高产物的选择性;随着能量密度增大至1000 J/L,甲苯转化率提高至88.0%,对CO2的选择性增大至39%;而气体流量增大,甲苯转化率降低;放电5m in内甲苯转化率迅速提高,10min后转化率趋于平稳;随着反应器内电极直径的增大,甲苯转化率先增大后减小,而碳平衡在内电极直径增大到一定值后基本稳定,说明内电极直径存在最佳值0.80mm.

This paper deals with the degradation of toluene gas by the photocatalysis coupled with dielectric barrier discharge （DBD）. It investigates the effect of the photocatalyst TiO2 driven by the DBD on the conversion rate of toluene at variable energy density, gas flow, discharge time and inner electrode diameter. The results show that （ 1 ） photocatalyst TiO2 improves the conversion rate of toluene and the selectivity of the products ; （2） when the energy density increases to 1000J/L, the conversion rate of toluene increases to 88.0% and the CO2 productivity to 39% ; （3） with the increase of gas flow, the conversion rate of toluene decreases; （4） the conversion rate of toluene increases rapidly in the first 5 minutes of discharge, then remains constant 10rain later; （5） the conversion rate of toluene at first increases and then decreases with the increase of inner electrode diameter; and （6） there is an optimal diameter （0. 80 mm） of inner electrode for toluene degradation because the carbon balance remains constant at a certain inner electrode diameter.