Synthesis of Hierarchical SAPO-5 & SAPO-34 Materials by Post-Synthetic Alkali Treatment and Their Enhanced Catalytic Activity in Transesterification

SAPO-5 and SAPO-34 materials were modified using post-synthetic alkali treatment, which results in the formation of hierarchical SAPO-5 and SAPO-34 materials. To test the generation of mesoporosity, the modified materials were thoroughly characterized using XRD, FE-SEM, TGA, ICP-OES, and N-2 adsorption/desorption techniques. Alkali treated SAPO-5 and SAPO-34 materials were utilized for the model reaction triacetin transesterification, under optimized conditions by varying the catalyst amount and reaction time: 90 % triacetin conversion with 66 % methyl acetate yield was achieved using modified SAPO-5 catalyst, whereas 68 % triacetin conversion with 37 % methyl acetate yield was achieved using modified SAPO-34 catalyst. The alkali treated SAPO-5 catalyst was stable up to the 4(th) cycle.