DBD协同NiO/α-Mn_(3)O_(4)催化降解气态邻氯甲苯

DBD Combined with NiO/α-Mn_(3)O_(4) Catalyzed the Degradationof Gaseous O-chlorotoluene

为提高介质阻挡放电(DBD)对氯代挥发性有机化合物(CVOCs)的处理效果,采用共沉淀法制备了NiO/α-Mn_(3)O_(4)复合催化剂,并协同DBD催化降解气态邻氯甲苯。通过X射线衍射仪、扫描电子显微镜以及比表面积与孔径分析仪对催化剂进行表征并探究了气体流速、外施电压、初始浓度和相对湿度等工艺参数对邻氯甲苯降解效率和能量产率的影响。结果表明:当Ni/Mn摩尔比为0.3,煅烧温度为400℃时,NiO/α-Mn_(3)O_(4)复合催化剂的催化性能最佳。邻氯甲苯的初始浓度为140 mg/m^(3),外施电压为8 kV,气体流速为0.9 m^(3)/h和相对湿度为65%时,邻氯甲苯的降解效率和矿化率较单独的DBD系统分别提高了33.9%和13.1%,O_(3)浓度和NO_(2)浓度分别降低了48.2 mg/m^(3)和12.3 mg/m^(3),CO_(2)选择性提高了12%。

In order to improve the treatment effect of dielectric barrier discharge(DBD)on chlorinated volatile organic compounds(CVOCs),the NiO/α-Mn_(3)O_(4) composite catalyst was prepared by co-precipitation method,and the gaseous o-chlorotoluene was catalyzed by DBD.The catalyst was characterized by X-ray diffraction(XRD),scanning electron micro⁃scope(SEM),and specific surface area and aperture analyzer(BET).The effects of gas flow rate,applied voltage,initial concentration,and relative humidity on the degradation efficiency and energy yield of o-chlorotoluene were investigated.The results showed that the NiO/α-Mn_(3)O_(4) composite catalyst had the best catalytic performance when the molar ratio of Ni/Mn was 0.3 and the calcination temperature was 400℃.When the initial concentration of o-chlorotoluene was 140 mg/m^(3),the applied voltage was 8 kV,the gas flow rate was 0.9 m^(3)/h and the relative humidity was 65%,the degradation efficiency and mineralization rate of o-chlorotoluene were increased by 33.9%and 13.1%,respectively,compared with that of DBD system alone.The concentration of O_(3) and NO_(2) decreased by 48.2 mg/m^(3) and 12.3 mg/m^(3) respectively,and the CO_(2) selectivity increased by 12%.