A method of synthesizing a NaY molecular sieve and the synthesized NaY molecular sieve

Abstract

The invention relates to a method of synthesizing a NaY molecular sieve and the synthesized NaY molecular sieve. The method includes following steps: a step of synthesizing a directing agent, namely a step of subjecting a silicon source and NaOH to mixing pretreatment, adding water and an aluminum source, mixing uniformly and ageing to obtain the directing agent, with the mole ratio of Na2O, Al2O3, SiO2 and H2O being 15-25:1:10-30:250-450; a step of preparing reactive gel, namely a step of adding a solid silicon source into a NaOH solution, pretreating to prepare hydrous silica gel, adding an aluminum source, mixing uniformly, adding the directing agent, stirring and mixing uniformly to obtain flow type solid-like reactive gel, with the total adding mole ratio of the Na2O, the Al2O3, the SiO2 and the H2O being 2-6:1:5.5-10.5:50-150; and a step of crystallizing, performing suction filtration and drying, namely a step of crystallizing the prepared solid-like reactive gel, filtering after crystallization is finished, washing and drying to obtain a product.

Description

technical field [0001] The present invention relates to the preparation of molecular sieves, specifically, a method for synthesizing NaY molecular sieves and the synthesized NaY molecular sieves, more specifically, mixing solid silicon-aluminum sources, deionized water and guiding agents evenly to obtain A flow-like solid-phase reaction gel, a new method for efficiently synthesizing NaY molecular sieves. Background technique [0002] Y-type molecular sieves are widely used in industry due to their high temperature stability and good catalytic activity. In the late 1950s, MILTON R M and BRECK D W successfully synthesized Y-type molecular sieves. Y-type molecular sieve replaces X-type zeolite as the main active component of the catalyst because of its high stability, high activity, anti-metal pollution and anti-sintering ability. In the early 1970s, GRACE Corporation of the United States synthesized NaY molecular sieves by the directing agent method. The raw material was wat...

AI Technical Summary

Problems solved by technology

Because the water glass system raw material itself contains a large amount of water, wherein the mass fraction of silicon dioxide is only 28%, and the viscosity of the synthesis system is too large to increase the solid content of the system, resulting in low solid content of the method, so the preparation of The single-pot yield of Y-type molecular sieve is 10-12% lower, and the utilization rate of silicon source is also low.

In order to avoid the loss of a large amount of silicon sources in the above processes, Y molecular sieves are mostly used to prepare the mother liquor for multiple reuses, which virtually brings process complexity and uncontrollable product properties.

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