Laminated crystal form SAPO-18 molecular sieve as well as synthesis method and application thereof

The invention discloses a laminated crystal form SAPO-18 molecular sieve as well as a synthesis method and application thereof. The synthesis method comprises the following steps: using an organic amine substance as a template agent and recording as OSDA, recording SiO2 as a silicon source, recording Al2O3 as an aluminum source, recording P2O5 as a phosphorus source, and using methylene blue as acrystal regulator and recording as R; preparing into synthetic sol according to the molar ratio of (1.5-3)OSDA:(0.15-1)SiO2:(0.85-1.2)Al2O3:(0.8-1.2)P2O5:(0.1-5)R:(50-100)H2O, and synthesizing the laminated crystal form SAPO-18 molecular sieve through dynamic crystallization. A catalyst synthesized in the invention can be well applied in multiple processes of petrochemical industry, coal chemicalindustry and fine chemical industry, and particularly has excellent catalytic activity and product selectivity in a reaction of preparing light olefins by catalytic cracking of methanol, dimethyl ether or a mixture of the two.