Synthesis of molecular sieves having the chabazite framework type and their use in the conversion of oxygenates to olefins

摘要

The synthesis of a crystalline aluminophosphate or silicoaluminophosphate molecular sieve having a chabazite-type framework type is conducted in the presence of an organic directing agent having the formula (I) [R¹R²R³N-R⁴]⁺X^- (I) wherein R¹, R² and R³ are independently selected from the group consisting of alkyl groups having from 1 to 3 carbon atoms and hydroxyalkyl groups having from 1 to 3 carbon atoms; R⁴ is selected from the group consisting of 4- to 8-membered cycloalkyl groups, optionally substituted by 1 to 3 alkyl groups having from 1 to 3 carbon atoms; 4- to 8-membered heterocyclic groups having from 1 to 3 heteroatoms, said heterocyclic groups being optionally substituted by 1 to 3 alkyl groups having from 1 to 3 carbon atoms and the heteroatoms in said heterocyclic groups being selected from the group consisting of O, N, and S; and aromatic groups optionally substituted by 1 to 3 alkyl groups, said alkyl groups having from 1 to 3 carbon atoms; and X^- is an anion.