Synthesis and characterization of SAPO-15 molecular sieve using hexamethylenetetramine template

Abstract

Silico aluminophosphate molecular sieve SAPO-15 was synthesized using hexamethylenetetramine template for the first time and characterized by various physico-chemical techniques such as XRD, SEM, TC/DTA, elemental analyses, FT-IR and 2 7 Al, 3 1 P and 2 9 Si MASNMR. The results were compared with AIPO 4 -15 molecular sieve of the same template. XRD and SEM show that the synthesized samples were highly crystalline. The structure is stable upto 250. TG/DTA reveals the presence of charge compensated templates. FT-IR spectrum of SAPO-15 shows the similarity of the framework with AIPO 4 -15. 2 7 Al MASNMR reveals the presence of aluminium in octahedral environment. 3 1 P MASNMR shows the presence of environmentally distinct two tetrahedral phosphorous species. 2 9 Si MASNMR indicates the presence of dominant Si : [4AI] species along with small Si : [4Si], Si : [3Si : Al], Si : [2Si : 2AI] and Si : [Si : 3AI] species.