填充床介质阻挡放电协同催化降解气态苯的研究

Research on Dielectric Barrier Discharge of Packed Beds and Benzene Degradation by Plasma Combined with Catalysts

利用介质阻挡放电产生的非平衡等离子体对气态苯的降解进行了实验研究.实验选用同轴圆筒式的填充床反应器,填充床内填充直径为3 mm的玻璃珠.实验采用的催化剂分别为负载量为8%的Mn/γ-Al2O3、Fe/γ-Al2O3、Co/γ-Al2O3催化剂.气体首先由反应器上方进入,通过石英玻璃管内侧放电区域,流经填充床放电区域后排出.实验分别考查了有无玻璃珠、苯初始体积分数及催化剂对苯降解效果的影响.在本实验中,玻璃珠的填充对苯的降解有促进作用.随着苯初始体积分数的增大,苯的降解效率逐渐降低.3种金属催化剂对苯的催化性能依次为:Mn>Co>Fe.

Experiments were performed to evaluate the efficiency of benzene decomposition by using packed-bed coaxial cylindrical dielectric barrier discharge reactor. The packed beds were filled with glass beads with a diameter of 3 mm. The catalysts prepared were 8% Mn/γ-Al2O3, 8% Fe/γ-Al2O3 and 8% Co/γ-Al2O3. The benzene was allowed to have access into the air inlet of the reactor before being introduced into the discharge regions in quartz glass tubes. Then it passed by discharge regions of the packed-beds, and finally flew out. The experiments were conducted to investigate the packed beds with or without glass beads, the initial concentration of benzene and the catalysts＇effect on the degradation of benzene respectively. The results indicate that higher efficiency is achieves with the packed beds filled with glass beads ; with the increasing of initial concentration of benzene, degradation efficiency of benzene decreases ; the order of the degradation efficiency of the catalysts is Mn 〉 Co 〉 Fe.