Synthesizing pure AlPO4-41 phase from the gels containing H3PO3 as the phosphorous source: A new reproducible route

The pure phase of AlPO4-41 molecular sieve has been synthesized in a new reproducible route by using Phosphorous acid (H3PO3) or the mixture of H3PO3 and phosphoric acid (H3PO4) as the phosphorus source. It was found that gels containing H3PO3 favor the formation of AlPO4-41. Raman and IR investigation showed that P(III) species has transformed to P(V) species after crystallization. AlPO4-41 has been obtained as a high crystallinity pure phase in a wide range of gel compositions. When the mixed phosphorus source of H3PO3 and H3PO4 were used, the crystallization of AlPO4-41 was accelerated.