Hollow-structure SAPO-34 molecular sieve prepared by utilizing MTO waste catalyst and preparation method and application of hollow-structure SAPO-34 molecular sieve

The invention provides a hollow-structure SAPO-34 molecular sieve prepared by utilizing an MTO waste catalyst, and a preparation method and application of the hollow-structure SAPO-34 molecular sieve. The preparation method comprises the following steps: mixing roasted waste MTO catalyst fine powder with water, and stirring; then adding organic amine and a phosphorus source and stirring to obtain an initial gel mixture; and crystallizing the initial gel mixture, at least drying the initial gel mixture, and roasting the initial gel mixture to obtain the SAPO-34 molecular sieve with the hollow structure. The average crystal particle size of the SAPO-34 molecular sieve with the hollow structure is 300-600 nm, and the diameter of the hollow structure is 50-200 nm. The molecular sieve disclosed by the invention is used as a catalyst in a methanol-to-olefin reaction, and shows relatively long catalytic life and relatively high low-carbon olefin selectivity, the total yield of ethylene and propylene is 87.5% or abov