MFI zeolite synthesis directly from silatrane via sol-gel process and microwave technique

Silatrane was synthesized from the reaction of SiO2 and triethanolamine using ethylene glycol as solvent under N-2 atmosphere. The obtained silatrane complex was further used as a Si source for MFI zeolite synthesis. The effect of Na+, OH-, and tetrabutyl ammonium hydroxide (organic template) concentration in the reaction mixture was studied. The reaction temperature was varied using the microwave heating technique. The effect of aging the reaction mixture at room temperature for varying times was also investigated. The rate of MFI formation decreases with increasing Na+, decreasing OH-, or lower template concentration. Higher temperatures correlate to shorter aging and heating times. At fixed temperature, longer aging times lead to shorter heating times. It was found that a longer aging time is more important to achieve high crystallinity than the heating time. (C) 2003 Elsevier B.V. All rights reserved.