SYNTHESIS OF ZEOLITE-BETA .2. FORMATION OF ZEOLITE-BETA AND TITANIUM-BETA VIA AN INTERMEDIATE LAYER STRUCTURE

The importance of layer structures for the synthesis of zeolite beta i s demonstrated. Zeolite beta is formed via a layered-aluminosilicate, which forms spherical agglomerates with diameters in the range 20-50 m u m. The transformation into the beta form occurs within the agglomera ted particles. The agglomerates are preserved at low temperatures of s ynthesis. A high intercrystalline volume is created in this way. The c onversion of zeolite beta into a layered SiO2 (organo-silicate) is obs erved at low synthesis temperatures and long times of synthesis. The w ell ordered SiO2 structure forms rectangular plates; the XRD patterns are presented. The structure collapses above 473 K with degradation of the template. A weak enrichment of polytype A was observed for some s amples crystallized at 368 K. The incorporation of titanium was studie d by UV-VIS spectroscopy and by Raman spectroscopic measurements under nearly in situ conditions.