甲苯吸附-DBD等离子体再生循环体系

采用Mn-Ag/HY和γ-Al2O3小球的混合物(质量比为1∶2)为催化剂,吸附气态甲苯,利用介质阻挡放电(DBD)等离子体对催化剂进行再生,并用SEM、BET和FT-IR仪器对再生后的催化剂进行表征,考察等离子体再生循环次数对催化剂结构及吸附性能的影响。结果表明:DBD等离子体可以有效地恢复催化剂的吸附能力,经过10次连续吸附-再生,催化剂仍保持较高的吸附水平,再生率可达71.47%；随再生次数增加,再生率下降,其中第1次的再生率最大,为100%；此外,将DBD再生10次的催化剂进行程序升温氧化(TPO),其吸附性能可得到恢复,再生20次后催化剂的再生率达62%以上。再生前后催化剂表征结果表明,Mn-Ag/HY与γ-Al2O3孔隙结构、表面化学官能团的变化以及其他残留有机物是导致再生率随着再生次数的增加而下降的原因。

Toluene adsorption-DBD plasma regenation cycled system

A mixture of Mn-Ag/HY and γ-Al2O3 (mass ratio 1∶2)as a catalyst was used to adsorb gaseous toluene. The used catalysts were regenerated by dielectric barrier discharge (DBD) plasma. The effects of plasma regeneration cycle number on the catalyst structure and absorptive property were studied based on the SEM, BET and FT-IR characterization of the fresh and used catalysts. Results showed that the adsorptive property of catalysts could be recovered by dielectric barrier discharge effectively, and the catalyst maintained a relatively high adsorption-ability with regeneration efficiency of 71.47% after 10 cycles of continuous adsorption-regeneration. The regeneration efficiency decreased with the increasing of regenerative cycles, and the maximum regeneration efficiency of 100% was obtained after the first cycle. In addition, the catalysts were temperature programmed oxidized after 10 cycles of regeneration, and the adsorptive property was almost recovered. After 20 cycles of regeneration, the regeneration efficiency was above 62%. Characterization of the catalyst before and after the desorption indicated that the change of pore structure of Mn-Ag/HY and γ-Al2O3, surface chemical functional group and residual organic matters are the main reasons for the decrease of regeneration efficiency.