双介质阻挡放电联合催化降解甲苯的副产物影响因素

Influence factors on by-products of toluene removal from gas by combining double dielectric barrier discharge with catalysis

双介质阻挡放电(DDBD)联合催化降解有机废气具有广阔的应用前景,探讨其副产物影响因素以便控制其浓度很重要。为此,采用自制高压电源与新型阵列式DDBD联合催化(以TiO2/Al2O3或Co/活性炭为催化剂)反应器,考察了其反应放电特性与波形,研究了甲苯初始浓度、气量、相对湿度和能量密度对脱除甲苯废气产生副产物(O3和NO2)的影响。结果表明:O3和NO2的浓度均随着甲苯初始浓度、气量、相对湿度的增加而降低,但随着能量密度的增加而升高。催化剂可以显著降低O3和NO2浓度,其中Co/活性炭在降低O3和NO2浓度方面效果最显著。当甲苯初始质量浓度为300mg/m^3、气体相对湿度为55%、气量为100m^3/h、能量密度为7.2J/L时,DDBD联合Co/活性炭催化剂脱除甲苯废气产生的O3质量浓度最低,为16.9mg/m^3;当甲苯初始质量浓度为50mg/m^3、相对湿度为85%、气量为100m^3/h、能量密度为7.2J/L时,DDBD联合Co/活性炭脱除甲苯废气产生的NO2质量浓度最低,为23.5mg/m^3。

Double dielectric barrier discharge(DDBD)with catalysis for degradation of organic gas technology has wide application prospect.It is very important to explore the influence factors of the by-products of toluene degradation by DDBD to control its concentration.A new type of reactor of array DDBD with catalysis was applied to remove toluene from gas,and the discharge characteristics and waveform of reactor were measured.The effects of the initial concentration of toluene,the gas flow rate,the air relative humidity and the specific energy density on the concentration of by-products(O3and NO2)in the process of toluene removal by DDBD were investigated.The results showed that the concentration of O3and NO2decreased with the increase of the initial concentration of toluene,the gas flow rate and the air relative humidity,but increased with the increasing of the specific energy density.The catalyst could significantly reduce the concentration of O3 and NO2,in which Co/activated carbon catalyst had the most significant effect in reducing the concentration of O3 and NO2.When the initial concentration of toluene was 300mg/m^3,the air relative humidity was 55%,the gas flow rate was 100m^3/h and the specific energy density was 7.2J/L,the lowest O3concentration was gained and equal to 16.9mg/m^3 in the removal of toluene from gas by DDBD combined with the Co/activated carbon catalyst.When the initial concentration of toluene was 50 mg/m^3,the air relative humidity was 85%,the gas flow rate was 100m^3/h and the specific energy density was 7.2J/L,the lowest NO2concentration was gained and equal to 23.5mg/m^3 in the removal of toluene from waste gas by DDBD combined with the Co/activated carbon catalyst.