Synthesis of hydrophobic zeolite X@SiO 2 core-shell composites

Abstract

Core-shell structures of zeolite X coated with silicalite as well as mesoporous (MCM-41) have been synthesized. Furthermore, the surfaces of the silicalite and mesoporous silica shells were silylated using organosilanes. The materials were characterized by X-ray diffraction, nitrogen adsorption/ desorption, scanning and transmission electron microscopy. The results show that the properties of zeolite 13X@silicalite and zeolite 13X@mesoporous silica core-shells composite structures are well maintained even after the modification. As expected, the shell thickness increased with increase in synthesis time, however, the micropore volume decreased. Silylation with smaller organosilanes (trimethyl..