介质阻挡放电联合催化臭氧化降解甲苯

Decomposition of toluene by dielectric barrier discharge comnbined with catalytic ozonation

采用介质阻挡放电区后结合MnOx/Al2O3/发泡镍去除甲苯,考察甲苯进气方式、臭氧产生方法及湿度对甲苯与O3同时去除的影响。结果表明,O3是等离子体区后催化降解甲苯的主要物种,介质阻挡放电联合催化臭氧化可实现甲苯及O3的同时高效去除。输入电压为9.0 kV时,甲苯的去除效率达92.8%,在80 min内O3的去除效率维持在99%以上。水蒸气对催化剂催化分解臭氧的活性没有直接的影响,O3浓度较高时湿度对甲苯降解效率的影响很小。GC-MS分析结果表明,甲苯降解的主要气相副产物有烷烃、酸、酮和含苯环有机物,提出了甲苯的降解途径。

Technology of dielectric barrier discharge（DBD）combined with MnOx/Al2O3/nickel foam in post-plasma was used to remove toluene.Effects of gas-feeding way of toluene,ozone generating method as well as humidity on the simultaneous removal of toluene and ozone were investigated.It was found that ozone was the main species responsible for the catalytic decomposition of toluene in post-plasma and high removal efficiencies of toluene and ozone could be realized simultaneously by DBD comnbined with catalytic ozonation.With input voltage of 9.0 kV,the toluene removal efficiency was up to 92.8% and that of ozone was above 99% within 80 min.Water vapor had no direct effect on the catalytic activity of catalyst towards ozone decomposition and humidity had little effect on the removal efficiency of toluene under higher ozone concentration.The results of GC-MS showed that main by-products in gaseous phase of toluene decomposition were alkanes,acids,ketones and ring-retaining organic compounds.Finally,the degradation way of toluene in this system was proposed.