Improving Toluene Capture Ability in Humid Environments by the Inner Surface Silanization of Zeolite

Abstract

Although Y zeolites are considered as promising adsorbents for capturing VOCs, their hydrophilic nature causes a significantly reduction in performance due to the pervasive water vapor in the VOCs stream. Herein, the inner and outer surfaces of HY are post-synthetic silanization with different silane agents, respectively. Methyl groups of TMeCS replace protons in hydroxyl groups on the inner surface of HY, accompanied by the formation of siloxane bonds. Attachment of methyl groups to the inner surface led to a significant reduction in both water affinity and ware diffusion rate, resulting in a notable enhancement of toluene adsorption capacity in humid environments. However, the outer surface silanization with TPrCS is ineffective in mitigating the detrimental impact of water on the toluene adsorption capacity. In this work, this regioselective silanization approach can provide a facile strategy for the adsorption/separation application of aluminosilicate zeolites.

Keywords: Zeolite, adsorption, Silanization, Hydrophobicity, Inner surface