Enhanced selectivity to propene in the methanol to hydrocarbons reaction by use of ZSM-5/11 intergrowth zeolite

摘要

Composite co-crystalline zeolites ZSM-5/11 were synthesised and tested in the methanol to hydrocarbons reaction. The composite materials consist of crystals with intergrowth between the MFI framework typical of zeolite ZSM-5 and the MEL framework of zeolite ZSM-11 and displayed selectivities to propene of up to 50%, and a relative increase over ZSM-5 of ca. 80% under the same reaction conditions. Comparison with the activity of commercial ZSM-5 permits the construction of a model that correlates the structure of these materials to the final selectivity. It is proposed that the enhanced selectivity is due to changes in the MFI/MEL contribution to the final structure.