介质阻挡放电协同催化对空气中苯的降解

Synergy of dielectric barrier discharges and catalysts for removal of benzene from air

为提高介质阻挡放电技术对空气中苯的去除效率,降低尾气中的残余有害气体的含量,采用等离子体结合二氧化锰或氧化铜/二氧化锰催化剂的方法.采用水热法和浸渍法分别合成了二氧化锰和氧化铜/二氧化锰催化剂,通过气相色谱仪和碘量滴定法测定了尾气中苯、二氧化碳、一氧化碳和臭氧的含量,研究了苯氧化降解过程等离子体与催化剂协同效应.结果表明,当不加催化剂时,随放电功率增加,苯的降解率可达68.2%,臭氧体积分数上升至595×10-6,二氧化碳的选择比为51.9%;采用氧化铜/二氧化锰催化剂对尾气中臭氧和一氧化碳降解最好,尾气中的臭氧降低为108×10-6,同时二氧化碳选择比提高至94.2%.

To improve the dielectric barrier discharge technology on benzene removal efficiency and reduce concentration of residual harmful gases in the tail gas, the method of plasma combined with MnO2 or CuO/MnO2 catalysts was used. MnO2 and CuO/MnO2 catalysts were prepared by hydrothermal method and impregnation, respectively. The concentration of residue benzene, CO2, CO and ozone was analyzed by gas chromatograph and iodine quantity method. The synergistic effect between plasma and catalysts in the benzene oxidation process was studied. Results show that when no catalyst is used, the degradation rate of benzene and the CO2 selectivity reach 68. 2% and 51. 9% respectively, but the concentration of ozone rises to 595× 10 ^-6 as the discharge power increasing. The CuO/MnO2 catalysts show higher catalytic activity for ozone decomposition and CO oxidation, the concentration of ozone reduces to 108× 10^-6 ,meanwhile the CO2 selectivity rises to 94.2 %.