微波催化燃烧气态甲苯特性及床层温度分布

采用浸渍法制备Cu-Mn-Ce/堇青石蜂窝催化剂，于微波催化燃烧装置中考察其对甲苯废气的催化活性与稳定性，并对固定床温度进行了测试分析.研究表明，微波加热下床层温度分布均匀，甲苯的最佳反应温度在230~270℃之间.当停留时间大于9.7s且床层温度高于270℃时，甲苯的降解率大于90%.铜锰铈单金属氧化物及其复合氧化物尖晶石是主要的活性组分，甲苯在其表面上进行准一级反应而被催化氧化.高温对催化剂结构有影响，但重复性试验证实了催化剂的高活性和良好的稳定性.本文为微波催化燃烧技术治理VOCs废气的中试研究及下一步的实际应用提供了理论支持.

Microwave catalytic combustion of gaseous toluene and distribution of bed temperature

In this study, Cu-Mn-Ce/cordierite honeycomb catalyst was prepared by an impregnation method and applied to catalyze gaseous toluene degradation through a fixed bed reactor under microwave heating. Catalyst activity and stability, and bed temperature were investigated simultaneously. It showed that bed temperature of cross section was nearly uniform under microwave irradiation and the optimal reaction temperature for toluene oxidation was between 230℃ and 270℃. The removal efficiency of toluene was higher than 90% when reaction retention time was more than 9.7seconds and bed temperature was higher than 270℃ concurrently. Monometallic oxides of copper, manganese and cerium and their composite oxides had spinel structures and were main active components. Toluene was oxidized on the surface of the active components that followed by pseudo-first order reaction. Cu-Mn-Ce/cordierite honeycomb catalyst had both high catalytic activity and good stability after eight-time repetitive tests although high temperature had a negative effect on the structure. The research work provides a theoretical support for the pilot-scale test and further practical application of microwave catalytic combustion technology in treating VOCs exhaust.