Abstract: The present invention provides a SAPO-34 molecular sieve with small crystal size and a hollow structure rapidly synthesized from a waste MTO catalyst and a method for preparation thereof. The method comprises of the following steps: calcining a waste MTO catalyst fine powder; mixing it with an inorganic acid solution to obtain a mixed solution; adding an organic amine and a phosphorus source to the mixed solution, and stirring it to obtain an initial gel mixture for SAPO-34 molecular sieve; crystallizing the initial gel mixture, and then drying the resultant to obtain a raw SAPO-34 molecular sieve powder; and calcining the raw powder obtained to obtain the SAPO-34 molecular sieve with small crystal size and a hollow structure.

Abstract: The present invention provides a long-lifetime SAPO-34 catalyst prepared from waste MTO catalyst as a raw material and a preparation method thereof. The method comprises the following steps: mixing the waste MTO catalyst fine powder with water; adding a phosphoric acid and an organic amine and stirring to obtain an initial gel mixture for SAPO-34 molecular sieve; crystallizing the initial gel mixture and then at least drying it to obtain a raw SAPO-34 molecular sieve powder; calcining the raw molecular sieve powder to obtain a SAPO-34 molecular sieve powder; then mixing it with a binder and a matrix carrier in water with stirring, and then aging it; and molding and then calcining it to obtain the long-lifetime SAPO-34 catalyst. The preparation method of the present invention uses MTO waste catalyst as a raw material to synthesize SAPO-34 molecular sieve in situ within a short time, and to prepare MTO catalysts having a long life and high selectivity for light olefins.