Method for preparing mordenite molecular sieve

Abstract

The invention relates to a method for preparing a mordenite molecular sieve. The method comprises the following steps of: dissolving an aluminum source in a sodium hydroxide solution, adding silicon sources, stirring at room temperature by strong magnetic force, and dispersing for a period of time; mixing the silicon sources which are dispersed uniformly and an aluminum source solution to form glue, adding a zeolite molecular sieve containing a five-membered ring as a crystal seed, stirring and mixing uniformly by the strong magnetic force at room temperature, and transferring the mixture into a reaction crystallization kettle, and performing crystallization reaction at the temperature of between 150 and 170 DEG C for 0.5 to 3 days; and performing suction filtration, washing and drying conventionally to obtain the mordenite molecular sieve. According to the method, an expensive organic amine template agent is not used as a structure guiding agent, and the zeolite molecular sieve which is wide in using, low in cost and readily available and contains the five-membered ring is used as the crystal seed to synthesize the mordenite molecular sieve with a high silica-alumina ratio directly, so the prepared mordenite molecular sieve has the advantages of high crystallinity and purity, controllable granular sizes and appearance, high yield, convenience for industrial production and the like.

Description

technical field [0001] The invention relates to the synthesis of zeolite molecular sieves, in particular to a synthesis method of mordenite molecular sieves. Specifically, it is a method for synthesizing mordenite molecular sieves by adding zeolite molecular sieves containing five-membered rings as crystal seeds without using organic ammonium as a structure-directing agent. Background technique [0002] Microporous molecular sieves have uniform pore structure, suitable acidity and good hydrothermal stability, and have become important petrochemical catalytic materials. Hydrogen-type mordenite with one-dimensional twelve-membered ring straight cylindrical channels (pore size 0.695 nm × 0.581 nm) exhibits excellent catalytic performance in toluene disproportionation, alkylation, isomerization of C8 aromatics and selective disproportionation of toluene . However, the mordenite molecular sieves synthesized by traditional methods usually have a relatively low silicon-aluminum r...

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Problems solved by technology

Chinese patent CN 1050011A reports the synthesis method of using cheap water glass as the silicon source mordenite as the seed crystal to prepare high silicon-aluminum ratio mordenite. The highest silicon-aluminum ratio can reach 25, but the synthetic particle size is larger than 1.0 μm

The results of literature and Chinese patent surveys show that the synthesis of mordenite with low cost and environmental friendliness has not been reported yet.

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