A kind of method adopting coal slime to prepare 4a type molecular sieve

Abstract

The invention discloses a method for preparing a 4A molecular sieve by adopting coal slime. The method comprises the steps: 1, grinding and sieving the coal slime, and calcining the sieved matter to obtain coal slime ash; 2, mixing a hydrochloric acid solution with the coal slime ash, reacting while stirring, filtering to obtain filter residue, and drying the filter residue for later use; 3, mixing NaOH with the dried filter residue, and performing alkali fusion to obtain slag; 4, adding sodium metaaluminate and water into the slag, and stirring uniformly to obtain a mixture; 5, ageing the mixture and crystallizing to obtain a solid-liquid mixture; and 6, filtering the solid-liquid mixture to obtain a filter cake, washing the filter cake with deionized water, and drying to obtain the 4A molecular sieve. By adopting the method, the coal slime can be sufficiently utilized, the utilization rate and the additional value of the coal slime are greatly improved, the preparation cost of the 4A molecular sieve is reduced, land occupation and environmental pollution caused by accumulating massive 4A molecular sieve are avoided, and the prepared 4A molecular sieve product has uniform granularity distribution and stable quality.

Description

technical field [0001] The invention belongs to the technical field of molecular sieve preparation, and in particular relates to a method for preparing 4A molecular sieves by using coal slime. Background technique [0002] 4A molecular sieve is an important inorganic microporous material, which has the characteristics of efficient selective adsorption, catalysis and ion exchange, and is widely used in daily chemicals, petrochemicals, medicine and environmental protection industries. Type 4A molecular sieves include natural zeolite molecular sieves and synthetic molecular sieves. The current industrial method for preparing 4A molecular sieves is to use pure chemicals such as sodium silicate, aluminum hydroxide, and sodium hydroxide as raw materials and prepare them by hydrothermal method. The method for synthesizing 4A molecular sieves with pure chemical reagents is mature, but its disadvantages are that it has strict requirements on the performance of the raw materials (the...

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Problems solved by technology

[0004] In recent years, some scholars have used coal series kaolin, coal gangue, and fly ash as silicon and aluminum sources to synthesize some types of molecular sieves, but there is no report on the preparation of 4A molecular sieves using coal slime as raw materials.

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