In order to increase the selective adsorption of volatile organic compounds (VOCs) on faujasite type zeolites, dealuminated ultrastable Y zeolites (USY) were prepared by the high-temperature hydrothermal technology. The results show that the microspores and surface area of USY decrease with the increase of Si/Al ratio of the USY, but secondary pores or mesoporous structures are formed after hydrothermal treatment. It was found that the ability of selective adsorption for toluene is enhanced with the increase of Si content in the zeolite framework. The amount of toluene adsorbed is 5.6 times higher than that of water adsorbed on USY (Si/Al=22) zeolites under the condition of RH=50%. The TG-DTG test shows that, after adsorption, the used USY (Si/Al=22) zeolites could be regenerated completely at low temperature (160℃), which allows it to be still reusable after several adsorption desorption cycles.%为提高Y分子筛对可挥发性有机废气的选择性吸附能力,采用高温水热处理技术对NaY分子筛进行骨架脱铝制备超稳Y分子筛(USY),并在固定床反应器中考察了USY在水汽存在下动态吸附低浓度甲苯的性能.结果表明,随着USY分子筛骨架Si/Al比的增加,虽然其微孔孔体积和比表面积发生了下降,但形成了较多的中孔结构.并且骨架硅含量增加后,USY对非极性的甲苯分子选择性吸附能力明显增加,当Si/Al为22左右,在相对湿度50％下,单位面积甲苯吸附量要比水吸附量大5.6倍.热重脱附研究表明,经过改性后,甲苯脱附温度可从NaY的300℃下降到超稳Y分子筛的160℃,具有优良的热再生性能.
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