Crystallization of the Granulated Molecular Sieve SAPO-11 Having High Crystallinity and a Hierarchical Pore Structure
A method for the synthesis of the granulated molecular sieve SAPO-11 having high crystallinity and a hierarchical pore structure was proposed for the first time. Crystallization is based on the synthesis of granules comprising 70 wt.% of powdered SAPO-11 and 30 wt.% of the silicoaluminophosphate binder, which transforms into SAPO-11 during crystallization and forms a joint system of intergrown silicoaluminophosphate crystals. This crystallization method makes it possible to obtain the granulated SAPO-11 having high crystallinity and phase purity; its specific surface area SBET is 212 m2/g, micro, meso- and macropore volumes are 0.08, 0.11 and 0.55 cm3/g, respectively. Meso- and macropores were shown to form between intergrown SAPO-11 crystals.