Preparation method of low-silicon SAPO-34 molecular sieve

Abstract

The invention discloses a preparation method of a low-silicon SAPO-34 molecular sieve, which is characterized by comprising the following steps: (1) uniformly mixing a silicon source, a phosphorus source and an aluminum source according to the mol ratio of (0.7-2)P2O5:(0.01-0.2)SiO2:Al2O3:(20-100)H2O, and drying to obtain silicon phosphorus aluminum dry glue with the solid content of not lower than 60%; (2) uniformly contacting and mixing the silicon phosphorus aluminum dry glue with a template and a silicon source to obtain a mixture, wherein the addition amount of the template is 1-2.5 mol on the basis of 1 mol of Al2O3 in the silicon phosphorus aluminum dry glue; and (3) putting the mixture in a closed reaction kettle, sectionally crystallizing under autogenous pressure, and recovering the product.

Description

technical field

[0001] The present invention relates to a kind of preparation method of SAPO-34 molecular sieve, relate to a kind of preparation method of low silicon SAPO-34 molecular sieve more specifically. Background technique

[0002] SAPO-34 molecular sieve is a phosphorus silicon aluminum molecular sieve developed by United Carbide Chemical Company in 1984. It belongs to the eight-membered ring chabazite CHA structure, cubic crystal system, the eight-membered ring pore size is 0.43nm, and the molecular dynamics of ethylene and propylene The diameter is similar. SAPO-34 molecular sieve has suitable acid strength, total acid content and good hydrothermal stability, and exhibits excellent catalytic performance in methanol to light olefins (MTO).

[0003] In the past thirty years, researchers at home and abroad have done a lot of work on the synthesis of SAPO-34 molecular sieves. There are many methods for the synthesis of SAPO-34 molecular sieve, such as hydrothermal s...

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