介质阻挡放电等离子体降解高浓度甲苯

Degradation of high concentration toluene with dielectric barrier discharge plasma

为解决喷漆和涂装废气中VOCs的污染,采用同轴圆管式介质阻挡反应器进行低温等离子体降解高浓度甲苯探索,研究了反应器参数(放电间距、放电长度)、操作参数(初始甲苯浓度、气体流量、输入功率)等关键参数对甲苯转化率和产物CO2选择性的影响。结果表明:放电间距过大或者过小都不利于甲苯的降解,放电长度的增加对其影响相对较小;输入功率越大,甲苯的降解效果越好,并且反应产物中臭氧的浓度越低,但气体流量及初始甲苯浓度的增加不利于甲苯的降解。最后对产物进行GC-MS检测,分析了甲苯降解机理。

To solve the pollution of VOCs generated in the paint and coating processes, a highly efficient reactor system is crucial important for the removal of VOCs. In this study, a coaxial circular tube dielectric barrier reactor was used to conduct the discharge experiment, and the effects of the reactor parameters（discharge gap, discharge length）and operating parameters（the initial concentration of toluene, gas flow rate and input power） on toluene degradation were extensively studied. The experimental results showed that neither a too large nor a too small discharge gap benefited the degradation of toluene, while the increase of the discharge length had a relatively smaller effect on toluene degradation. Moreover, it was found that higher input power will improve the degradation of toluene and lower the ozone concentration in the exhaust gas. However, the increase of gas flow rate and initial toluene concentration were not conducive to toluene degradation. Finally, the mechanism of toluene degradation was discussed by analyzing the products distribution according to GC-MS results.