Core-shell structured Y zeolite/hydrophobic organic polymer with improved toluene adsorption capacity under dry and wet conditions

Abstract

Zeolites with high specific surface area and good stability are considered ideal adsorbent for volatile organic compounds (VOCs) adsorption. However, the hydrophilicity of zeolites surface limits their practical application because of the competitive adsorption between water and VOCs. In this work, we reported a strategy to synthesise Y zeolite and hydrophobic organic polymer core-shell composites (Y@St-DVB), which significantly improved the hydrophobicity and toluene adsorption capacity of Y zeolite. The TEM results showed that hydrophobic organic polymer was uniformly coated on the external surface of Y zeolite through the bridging effect of phenylsilane. The adsorption capacity of Y@St-DVB-12h was 69.9% higher than that of Y zeolite at dry condition, and increased about 96% under 90% relative humidity (RH). It also exhibited excellent adsorption and desorption performance under 60% RH, which was suitable for the practical application. In addition, such composite strategy was suitable for other zeolites (EMT, ZSM-5, and Beta zeolite) to realise hydrophobic modification, which increased the adsorption capacity under wet conditions. This work not only proposes a new hydrophobic zeolite-based VOCs adsorbent, but also provides a new idea for the preparation of a series of hydrophobic adsorbents.