A method for the independent preparation of pure silicon or heteroatom stt molecular sieves

Abstract

The application belongs to the field of molecular sieve preparation, and provides an independent preparation method of pure-silicon or heteroatom STT molecular sieve, comprising the following steps: (1) uniformly mixing a silicon source, a structure directing agent and water to obtain a precursor, hydrothermally crystallizing the precursor, filtering, washing, drying and calcining to obtain Si-MWW molecular sieve; (2) using a crystal transformation method, taking the Si-MWW molecular sieve as a silicon source, adding different heteroatom sources, structure directing agents and water respectively, uniformly mixing, hydrothermally crystallizing, centrifuging, washing, drying and calcining to obtain Si-STT, Al-STT, B-STT and Zr-STT molecular sieves. The application breaks through the problems in the traditional synthesis method of STT molecular sieve, such as long synthesis period, need of fluorine medium assistance and easy generation of impurity phases, and can efficiently realize the synthesis of pure-phase STT and the introduction of heteroatoms.

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