Method for synthesizing Omega zeolite molecular sieve

Abstract

The invention discloses a method for quickly synthesizing an Omega zeolite molecular sieve, which comprises the following steps: uniformly mixing an aluminum source, an alkali source and deionized water, and adding a silicon source with stirring; continuously stirring the solution until the solution is uniform to form silica-alumina gel, adding a certain amount of choline into the silica-alumina gel, and then stirring the gel; adding zeolite molecular sieve raw powder into a reaction kettle, then putting the gel into the reaction kettle, crystallizing the gel for 0.25-2 days at the temperatureof 100-180 DEG C, and carrying out suction filtration, washing and drying on the product to obtain the Omega zeolite molecular sieve raw powder. The Omega zeolite molecular sieve is rapidly synthesized under hydrothermal synthesis conditions by taking choline as a template agent, has the advantages of short synthesis period, environmental friendliness and low cost, and conforms to the target of green sustainable development.

Description

technical field [0001] The invention belongs to a molecular sieve preparation method, in particular to a method for synthesizing an Omega zeolite molecular sieve with a green and cheap template agent. Background technique [0002] Zeolite molecular sieves are widely used in petrochemical and fine chemical processes because of their high specific surface area, large pore volume, and adjustable acid density. Omega zeolite molecular sieve has a one-dimensional 12-membered ring channel structure, which belongs to P6 3 / mmc space group. The pores of Omega zeolite catalysts have excellent shape selectivity and are used in the important hydroisomerization reactions in industrial catalysis. [0003] In the current reports on the preparation of Omega zeolite molecular sieves, commonly used organic templates include tetramethylammonium hydroxide, dioxane, piperazine and the like. It is worth noting that tetramethylammonium hydroxide is toxic and highly corrosive, which will acceler...

AI Technical Summary

Problems solved by technology

It is worth noting that tetramethylammonium hydroxide is toxic and highly corrosive, which will accelerate the consumption of production equipment and pollute the environment during the synthesis of Omgea zeolite molecular sieve; dioxane is toxic and chemically carcinogenic, and the synthesis The route of Omega zeolite molecular sieve does not meet the requirements of green environmental protection; piperazine is combustible when exposed to high heat, and decomposes to release toxic gas, which greatly affects the ecological environment in the process of synthesizing Omega zeolite molecular sieve

The above-mentioned organic templates have the disadvantages of high cost, serious environmental pollution, and long synthesis cycle, which are not conducive to the industrial production of Omega zeolite catalysts.

Recently, researchers have discovered that Omega zeolite can also be synthesized by the template-free seed crystal method, but the required crystallization time is longer and the resulting product is more aluminum-rich, which affects its industrial application to a certain extent.

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