催化剂对低温等离子体降解吸附态甲苯的影响

Influence of catalyst on decomposition of adsorbed toluene with non-thermal plasma

采用线管式介质阻挡反应器对低温等离子体循环降解甲苯进行研究,考察了吸附存储量、循环背景气体及不同催化剂成分对吸附态甲苯降解效果及副产物的影响,并进行了催化剂XRD分析及降解产物FT-IR分析。结果表明,氧气为循环背景气体时甲苯降解效果比空气时好。FT-IR分析显示催化剂的加入可使甲苯充分降解,显著提高COx产率、CO2选择性,减少副产物O3、N2O排放量。相同条件下,单组分催化剂对应COx产率依次为:Ce>Mn>Ag>Co,CO2选择性依次为:Ag>Mn>Co>Ce。双组分催化剂Mn/Ag、Ce/Ag可同时保持较高的COx产率和CO2选择性,氧气背景时COx产率分别达到80%、82%,CO2选择性均达到99.7%以上。空气背景时,Co对N2O的抑制效果最好,3组分催化剂Mn/Ag/Co、Ce/Ag/Co在保持较高的COx产率和CO2选择性同时可有效抑制N2O。

This study employed nonthermal plasma to decompose toluene using a wire-pipe dielectric barrier reactor. The effects of the amount of adsorbed toluene, background gas, and catalysts with different components on the decomposition of adsorbed toluene and its by-products were investigated, and XRD analysis of the catalyst and FT-IR analysis of the degradation products were also conducted. It was found that Ozatmosphere exerted a better effect on toluene decomposition than air atmosphere. FT-IR indicated that the addition of a catalyst could significantly enhance the decomposition of toluene, with an increased COx yield and CO2 selectivity, while 03 and N20 were reduced. Under the same conditions, in the case of a single-component catalyst, the COx yield and CO2 selectivity could be respectively ranked as follows ： Ce 〉 Mn 〉 Ag 〉 Co and Ag 〉 Mn 〉 Co 〉 Ce. When oxygen atmosphere was utilized along with a two-component-catalyst （Mn/Ag or Ce/Ag） , a high CO~ yield and COa selectivity were achieved, where the COx yields respectively increased to 80% and 82% and the CO2 selec- tivity increased to 99.7%. Under air atmosphere, Co exerted the highest inhibitory effect on N20. The three- component-catalysts （Mn/Ag/Co and Ce/Ag/Co） could maintain a high COx yield and CO2 selectivity and effec- tively inhibit N2O.