Synthesis of hybrid zeolites using a solvent-free method in the presence of different organosilanes

Hybrid sodalite zeolites were produced by grinding, homogenizing and heating the reactants, including different organosilanes, without the addition of solvent (water). Hybrid sodalite zeolites were produced in the presence of triethoxy(octyl)silane (C8Si), 3-chloropropyltrimethoxysilane, triethoxymethylsilane, hexamethyldisiloxane, octadecyltrimethoxysilane (ODS) and chlorotrimethylsilane. The resulting hybrid zeolites were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, Xray diffraction, water contact angle, small-angle X-ray scattering and thermogravimetric analysis. The presence of 6 wt.-% of organosilane introduced in the reaction medium caused no disturbance to the crystal growth. All materials exhibited dense, spherical and uniform particles, with slightly rough surfaces according to SAXS measurements. In the case of octadecylsilane, it appears that the alkyl chains are well packaged and organized, while for octylsilane, a more disordered structure seems to be present. Only organosilanes with longer alkyl chains (C8Si and ODS) show hydrophobic properties. The solvent free method proved to be effective in synthesizing samples with good crystallinity and hydrophobic characteristics. This synthesis method was shown to be efficient, fast, economical and environmentally friendly. (c) 2016 Elsevier Inc. All rights reserved.