Method for preparing 13X molecular sieve through using high-alumina fly ash, and 13X molecular sieve

Abstract

The invention provides a method for preparing a 13X molecular sieve through using high-alumina fly ash, and the 13X molecular sieve. The preparation method comprises the following steps: mixing the high-alumina fly ash with an alkali solution for a pre-desiliconization reaction, and filtering to obtain a desiliconized solution; mixing the desiliconized solution with white carbon black to obtain a modified desiliconized solution; mixing the modified desiliconized solution with an aluminum sauce to obtain a silicon and aluminum sol; and crystallizing the silicon and aluminum sol, filtering, washing, and drying to prepare the 13X molecular sieve. The invention also provides the 13X molecular sieve prepared through the preparation method.

Description

technical field [0001] The invention relates to a method for preparing 13X molecular sieve and 13X molecular sieve, in particular to a method for preparing 13X molecular sieve and 13X molecular sieve by using high-alumina fly ash. Background technique [0002] As a kind of industrial waste, the output of fly ash is astonishing, and the accumulative stockpile in China has reached billions of tons. Therefore, how to properly dispose or utilize fly ash has become an urgent problem to be solved. In the industry, industrial raw materials containing silicon and aluminum or silicate minerals are generally used as raw materials to prepare molecular sieves, and the production cost is relatively high. Fly ash contains a small amount of Fe 2 o 3 , CaO and MgO and other impurities, contains a large amount of SiO 2 and Al 2 o 3 (The content of the two can reach more than 80%). Therefore, people try to use fly ash as a resource according to its characteristics, and use it to prepare ...

AI Technical Summary

Problems solved by technology

However, since the crystalline quartz and mullite in the fly ash are not easy to be activated, the molecular sieves synthesized by this method have low purity; the two-step method mainly uses lye to dissolve the soluble active components in the fly ash, and then filters And adjust the silicon-aluminum ratio of the filtrate, and then obtain a high-purity molecular sieve through hydrothermal reaction, but this method only utilizes the soluble silica in the fly ash, so the overall conversion rate of fly ash to form zeolite is on the low side

[0005] The method of preparing molecular sieves from the desiliconization solution produced in the pre-desilication process in the process of extracting alumina from high-alumina fly ash is consistent with the two-step hydrothermal method. Although the synthesized molecular sieve has the advantage of high purity, due to the di The silicon oxide content generally does not exceed 85g / L, which makes the single-pot yield of molecular sieve synthesis low, resulting in high energy consumption per unit output

Images