Small crystal grain molecular sieve preparation method

Abstract

The invention discloses a method for preparing the NaY molecular screen of high alumina silica ratio and fine grain, firstly synthesizing NaY molecular screen guilding agent according to current technology, then producing gel with sodium silicate, guilding agent, acid aluminium salt and sodium metaaluminate, blooming the gei under the temperature of 50-100 Deg C for 0-70 hours, adding some silicon, then blooming continuously under temperature of 90-120 Deg C for 0.5-50 hours, finally filtering, washing and drying. The NaY molecular screen with the alumina silica ratio being 5.2-7.0, and fine grain being 100-400 nm can be prepared by using the method in this invention.

Description

technical field [0001] The invention relates to a preparation method of NaY molecular sieve. More specifically, it relates to a preparation method of a small-grain high-silicon NaY molecular sieve. Background technique [0002] As the core technology of the oil refining industry, catalytic cracking and its catalysts have attracted much attention. As the catalytic cracking feedstock becomes heavier, the proportion of macromolecular hydrocarbons with an average size above 2nm in the feedstock continues to increase. The Y-type molecular sieve, which is the main active component of the catalytic cracking catalyst, has a pore size of only 0.7nm. Obviously, a large number of raw material molecules cannot enter the channels of the Y-type molecular sieve for reaction. Although the macromolecules in the feedstock can be precracked on the catalyst substrate, the diffusion effect still has a significant impact on the catalytic cracking reaction. The small-grain Y-type molecular siev...

AI Technical Summary

Problems solved by technology

[0040] The above-mentioned methods for synthesizing small-grain faujasite can often only synthesize X-type molecular sieves or SiO 2 / Al 2 o 3 Y-type molecular sieve with lower silicon-aluminum ratio <5