Preparation method of appearance-controllable L zeolite

Abstract

The invention discloses a preparation method of appearance-controllable L zeolite. The method uses villaumite as an additive; a synthesis method of L zeolite appearance regulation through sectioned crystallization is used. The method comprises the concrete steps of mixing a silicon source with an aluminum source; performing static aging at 5 to 60 DEG C for 2 to 72 hours to obtain a guiding agent;then, mixing the silicon source, the guiding agent, the aluminum source and villaumite to obtain glue, wherein the mole ratio of all ingredients in the reaction mixture gel is 8 to 20K2O:Al2O3:20 to60SiO2:120 to 800H2O: 0.03 to 0.3F<->; then, performing two-stage static crystallization at different temperatures, wherein the first-stage crystallization temperature is 5 to 60 DEG C, and the firststage crystallization time is 12 to 48 hours; the second stage crystallization temperature is 120 to 180 DEG C, and the second stage crystallization time is 12 to 72 hours; finally, performing filtering, washing and drying to obtain an L zeolite molecular sieve. The obtained molecular sieve has high relative crystallinity degree; the appearance is in a particle shape, a round cake shape and a double-cone shape. The preparation method has the advantages that the raw materials can be easily obtained; the preparation cost is low; good industrial application prospects are realized.

Description

technical field [0001] The invention belongs to the field of molecular sieve materials and preparation thereof, in particular to a method for preparing L zeolites with different shapes. Background technique [0002] L zeolite is a kind of artificial synthetic zeolite, it has unique adsorption performance and catalytic performance, and also has good thermal stability. It is a kind of catalytic material with excellent thermal stability, which can be used to prepare Catalysts for hydrocarbon conversion processes such as structuring and alkylation. The skeleton structure of L zeolite is composed of cannonite cages and double six-membered rings. It was first synthesized by Breck and Flanigen in 1965. Subsequently, people have carried out a lot of research on the synthesis of L zeolite. Usually, L zeolite can use silica sol, white carbon black or water glass as a silicon source, potassium metaaluminate or sodium metaaluminate as an aluminum source, and potassium hydroxide and hydr...

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Problems solved by technology

[0004] CN200810154213 uses silica sol as a silicon source, potassium metaaluminate as an aluminum source, and adds a quantitative directing agent during the synthesis process to obtain L zeolite with a particle size of 200-300nm, but there is a problem of relatively low crystallinity

[0005] In a large number of synthetic methods, each synthetic method can only obtain molecular sieves with a single morphology, and the morphology of molecular sieves cannot be modified through the control of the synthesis process to meet the needs of intolerant reactions.

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