V2O5-WO3/TiO2催化剂用于对二甲苯氧化去除实验研究

Experimental Study on Oxidation Removal of Para-Xylene Using V2O5-WO3/TiO2 Catalyst

废弃V2O5-WO3/TiO2SCR催化剂已经成为燃煤电厂新的环保问题。开发废弃SCR催化剂用于催化氧化挥发性有机物(VOCs)的新方法。先对比了废弃和新鲜V2O5-WO3/TiO2催化剂催化氧化废气中对二甲苯的去除效果,发现两者的去除效果基本相同。然后重点研究了反应温度、氧气含量、对二甲苯初始浓度等关键工艺参数对对二甲苯去除效果的影响。研究结果表明:对二甲苯去除率受反应温度影响较大,在100℃以上时随反应温度的增加而增加;而氧化产物CO2选择性在200℃以上时才有显著增加;氧气体积分数的增加能够提升对二甲苯去除率,特别是氧气体积分数从0%增加到5%时,对二甲苯去除率明显提升。对二甲苯去除率和COx选择率随着对二甲苯初始浓度的增加而下降。

V2O5-WO 3/TiO 2 waste SCR catalyst has become a new environmental protection problem in coal-fired power plants.A new method to reuse the waste catalyst for the catalytic oxidation of volatile organic compounds(VOCs)was developed.At first,a comparison of new and waste V2O5-WO 3/TiO 2 catalysts on catalytic oxidation of para-xylene in a waste gas was carried out;it was found that they have almost the same removal effects.Then,the influences of key process factors,such as reaction temperature,oxygen concentration and para-xylene initial concentration on para-xylene decomposition were studied.It was found that the para-xylene conversion rate was greatly affected by the reaction temperature,and increased with increasing reaction temperature above 100℃.While the selectivity of oxidation product CO 2 increased obviously at a temperature higher than 200℃.The increase in oxygen concentration could promote para-xylene conversion,especially,when the oxygen concentration increased from 0%to 5%,para-xylene conversion was significantly improved.The para-xylene conversion and CO x selectivity decreased with the increase of para-xylene initial concentration.