In situ synthesis of highly qualified TBA-silicalite-2 zeolite membranes on biomorphous charcoal supports

Highly qualified tetrabutylammonium (TBA)-silicalite-2 layers were successfully grown via a simple in situ hydrothermal synthesis in microchannels of biomorphic porous charcoals from the reactant system TBAOH-TEOS-H₂O. All the charcoal supports were previously oxidised and vacuum-infiltrated to favour the anchoring of the silicalite-2 crystals. The as-prepared products were characterised in detail by power X-ray diffraction, Fourier transform infrared spectra and field emission scanning electron microscopy. The experimental results indicate that the uniform and dense TBA-silicalite-2 zeolite membranes consisting of spherical and columnar crystals were prepared on the inner surface of biomorphic charcoal by different synthesis temperatures and times. As a new zeolite adsorbent hybrid material, the silicalite-2 zeolite/porous charcoal composite was evaluated by the N₂ adsorption-desorption isotherm tests, which exhibit high-Brunauer-Emmett-Teller surface area and microspore volume with 168-m²/g¹ and 0.05 cm³/g¹, respectively. The obtained charcoal-zeolite membranes may have potential applications in catalysis and separation.