The invention relates to a nanometer needle-shaped SAPO-34
molecular sieve, as well as preparation and application thereof. A gel decondensation
hydrothermal synthesis method is adopted and particularly comprises the following steps: (1) mixing an aluminum source, a
phosphorus source, a
silicon source, deionized water and a template agent, heating and stirring to obtain gel A; (2) adding excessive HF solution into the gel A, wherein the gel is decondensed into a solution at this moment; (3) performing hydrothermal
crystallization: transferring the solution obtained in the step (2) into a
polytetrafluoroethylene reaction kettle, performing high-temperature
crystallization, rapidly cooling after the
crystallization is completed, filtering and washing the obtained
solid,
drying and
roasting to obtain the nanometer needle-shaped SAPO-34
molecular sieve. The preparation process is simple and easy to operate, and the
molecular sieve has important application in
methanol to olefin reaction; meanwhile, due to the special shape, the molecular
sieve can serve as a carrier of catalyst
active components and has potential industrial application prospect.