Synthesis of SAPO-41 from a new reproducible route using H3PO3 as the phosphorus source and its application in hydroisomerization of n-decane

In the new reproducible route, phosphorous acid (H3PO3) or the mixture of H3PO3 and phosphoric acid (H3PO4) are used as the phosphorus source to synthesize microporous silicoaluminophosohates. It is found that gels containing H3PO3 favor the formation of SAPO-41 materials. With only H3PO3 as the phosphorus source, pure SAPO-41 phase can be prepared with high crystallinity. When the mixture of H3PO3 and H3PO4 is used as the phosphorus source, the crystallization of SAPO-41 can be accelerated. Raman and XRD results show that SAPO-41 can be formed after crystallizing for 12 h. The dosage of the template di-n-propylamine (DPA) can be reduced in the mixed phosphorus source system. The SAPO-41 has been used to prepare catalysts for the hydroisomerization of n-decane. High selectivity of isomerization (89.5%) has been observed even at high conversion (88%) over the Pt/SAPO-41.

Graphical abstractFrom H3PO3 containing gel to SAPO-41 molecular sieve. In the new reproducible route, Phosphorous acid (H3PO3) or the mixture of H3PO3 and phosphoric acid (H3PO4) are used as the phosphorus source to synthesize microporous silicoaluminophosohates. It is found that gels containing H3PO3 favor the formation of SAPO-41 materials. Figure optionsDownload full-size imageDownload as PowerPoint slide