非平衡等离子体联合技术降解甲苯气体

采用了自制的纳米钛酸钡基介电材料作为催化剂,以电工陶瓷拉西环作为载体,利用介质阻挡放电产生的非平衡态等离子体对常压下流动态含甲苯的空气进行处理,研究了电场强度、流速、初始浓度及不同填料情况下甲苯的降解及臭氧产生情况,初步探讨了等离子体催化降解甲苯的机理,并进行了产物分析.实验结果表明,电场强度小于13kV·cm-1时,甲苯降解率和臭氧产生浓度随电场强度的提高而上升,随气速和初始浓度的增加而降低;不同填料下降解率及臭氧浓度由大到小排序为有催化剂填料、普通填料、无填料,有催化剂存在时(电场强度为14kV·cm-1,流速为0.3 m3·h-1,甲苯浓度为600 mg·L-1),甲苯降解率最高可达95%.当电场强度>13kV·cm-1时,臭氧浓度因受到过量的高能电子攻击而发生分解.表现为臭氧浓度随电场强度的继续增加而降低.因此,电场强度为13kV·cm-1时,产生的臭氧浓度最高.

Toluene decomposition in a non-equilibrium plasma

A series of experiments were performed in a non-equilibrium plasma reactor to remove toluene from a gaseous influent at room temperature and atmospheric pressure by decomposition due to dielectric barrier discharge(DBD).We studied the decomposition efficiency of toluene and the output of ozone under different electric field strengths,influent flow rates,influent toluene concentrations and packing materials.Decomposition efficiency of toluene and output of ozone increased with increasing voltage and/or influent flow rate,but decreased with a rise in influent toluene concentration.Placing packing materials in the plasma reactor improved the toluene decomposition efficiency and packing materials containing catalysts resulted in greater enhancement of decomposition efficiency.More ozone was produced in the reactor with catalyst-containing packings and high voltages,up to 13 kV·cm^-1.The mechanism of toluene decomposition due to plasma and catalyst actions is proposed.Toluene decomposition efficiency in the influent(electric field strength= 14 kV·cm^-1,flow rate = 0.3m³·h^-1,toluene concentration= 600mg·L^-1)was up to 95% in the plasma with catalyst-containing packing material.