Crystalline intergrowth material, its synthesis and its use the conversion of oxygenates to olefins

摘要

A silicoaluminophosphate molecular sieve is disclosed that comprises first and second intergrown phases of a CHA framework type and an AEI framework type, wherein said first intergrown phase has an AEUCHA ratio of from 5/95 to 40/60 as determined by DIFFaX analysis, the second intergrown phase has an AEI/CHA ratio of 30/70 to 55/45 as determined by DIFFaX analysis and said molecular sieve has a silica to alumina molar ratio (Si/Al2) from 0.13 to 0.24.