The Investigation of the Effects of Adsorbed Molecules on Local Structure of Zn-SAPO-34 by Multinuclear Solid State NMR

摘要

Silicoaluminophosphate molecular sieve SAPO-34, an isotype of the chabazite, is considered as a promising catalyst for methanol conversion to light olefins1. It is well known that SAPO-34 is very sensitive to moisture at room temperature after template removal. The incorporation of transition metal ions into framework sites of silicoaluminophosphates is also of interest for the design of novel catalysts. In this study, the changes in the local environment of Si and Al of Zn-SAPO-34 in the presence of different adsortates were investigated by solid state NMR. The calcination and presence of adsorbed phases could lead to rearrangement of Si pecies in framework and the formation of various Al species.