The mesoporous molecular sieves of MCM-41 and SBA-15 with ordered pore structure were synthesized by the template method, and their dynamic adsorption performances for some VOCs, such as toluene, o-xylene and mesitylene, were studied. The results show that the MCM-41 is prior to adsorb the VOCs with medium and low concentrations, because the attractive forces from pore walls of MCM-41 is enhanced by its small pore diameter. The adsorption characteristics of VOCs on MCM-41 could be attributed to the typical type Ⅰ isotherm from IUPAC. The SBA-15 involves both mesopores and micropores, and is more appropriate for the adsorption of VOCs with higher concentrations and macromolecules. Furthermore, SBA-15 is also suitable for the adsorption of VOCs with low concentrations. The adsorption isotherms of VOCs on SBA-l5 are that of typical type Ⅳ.The dynamic adsorption processes on MCM-41and SBA-15 could be simulated by Yoon-Nelson model. The breakthrough curves of VOCs adsorption on these mesoporous molecular sieves could be predicted by using this model and its related parameters accurately.%采用模板剂法制备了具有规整孔道的MCM-41和SBA-15介孔分子筛,考察了两种介孔分子筛动态吸附甲苯、邻二甲苯、均三甲苯的特性.结果表明,MCM-41平均孔径小,孔壁叠加作用力强,更适合吸附中、低浓度的VOCs,对芳烃类VOCs为典型的I型吸附等温线;SBA-15具有微孔和介孔共存的特点,平均孔径大,对大分子和高浓度的VOCs具有更好的吸附能力,同时也可有效地吸附低浓度VOCs,对芳烃类VOCs为典型的Ⅳ型吸附等温线.通过Yoon-Nelson模型对MCM-41和SBA-15动态吸附过程的拟合,得出的吸附模型参数可以较为准确地预测VOCs在介孔分子筛上的吸附穿透曲线.
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