Facile synthesis of VFI molecular sieve in the presence of triethylamine.

ABSTRACT

Aluminophosphate (AIPO) molecular sieve having extra-large pore (VFI structure with 18 membered rings) can be synthesized readily at 110 or 120 degrees C under microwave irradiation from a gel containing triethylamine (TEA) as a template or structure-directing agent. At high temperature of 130 degrees C, the VFI transforms into AFI with the increase of reaction time since the relative stability of VFI is less than that of AFI. Due to the rapid crystallization involved in the microwave method and instability of the porous material with extra-large pore (in this study, VFI structure), the material can be selectively synthesized only by microwave irradiation. The synthesized VFI from gel containing TEA is very stable that can be dried at 100-160 degrees C at atmospheric pressure without the phase-transformation into AIPO-8.