低温等离子体协同钒钛催化剂降解甲苯试验

    Removal of Toluene by Non-thermal Plasma Coupled With V-Ti Catalysis

    • 摘要: 采用可调频高压电源、自制线管式介质阻挡放电反应器,以挥发性有机化合物(VOCs)代表物质——甲苯为去除对象,考察了低温等离子体协同不同类型催化剂降解甲苯性能.对反应器能量密度、能量效率、副产物臭氧生成情况进行了考查比较.筛选出性能较优的催化剂,对其进行了稳定性实验,并对反应产物进行了测定分析.研究结果表明:填充钒钛系催化剂对甲苯的降解有明显的促进作用,能量密度和臭氧生成量有所降低,能量效率有明显提高.针对V2O5-TiO2/γ-Al2O3催化剂进行的稳定性实验研究表明:甲苯去除率随反应时间延长而缓慢下降,表明催化剂存在失活现象,可能是由甲苯降解形成的副产物在催化剂表面积聚而覆盖催化剂反应活性位造成的.500℃空气气氛下焙烧4 h能使催化剂的活性恢复至初始水平.

       

      Abstract: Removal of toluene by the combination of non-thermal plasma( NTP) and various catalysts was investigated in this study. Self-made wire-cylinder dielectric barrier discharge( DBD) reactor energized by AC power supply was used in our experiment. Specific energy density( SED),energy efficiency(EY) and O3 concentration of different reactor were investigated. The better catalyst was chosen,catalyst stability test was carried out,and the by-products in the reaction were determined and analyzed. The results show that compared with γ-Al2O3,V2O5-TiO2/γ-Al2O3 catalysts can enhance the conversion of toluene,decrease SED and O3 concentration and enhance EY. Stability test of V2O5-TiO2/γ-Al2O3 catalyst show that toluene conversion decreases slowly with the reaction time,which indicates that the catalyst suffers slow deactivation,probably due to the accumulation of by-products over the catalyst surface. After calcinations in air for 3 h at 500 ℃,activity of the catalyst can be recovered.

       

    /

    返回文章
    返回