H-ZSM-34 molecular sieve and preparing method thereof

Abstract

The invention discloses a preparing method of an H-ZSM-34 molecular sieve. The preparing method of the H-ZSM-34 molecular sieve comprises the steps of preparing a mixture A from n(Al2O), n(Na2O), n(K2O), n (SiO2) and n (H2O) according to the proportion of 1:5.1:9.13:10.54:129.98, adding an aluminum source into an aqueous solution, continuing to add an alkaline source and a silicon source, and after stirring, ageing to obtain a clarified crystal seed solution; adding sodium hydroxide and water-soluble silica gel into an aqueous solution with a certain volume, after stirring, adding aluminum sulfate crystals and a crystal seed solution with a certain volume in sequence, stirring at the room temperature, putting the mixture into a kettle, conducting crystallization, taking the solution out ofthe kettle, conducting suction filtration and washing, and conducting drying and roasting to obtain Na-ZSM-34; adding a certain amount of Na-ZSM-34 into a 1mol / L ammonium nitrate solution according to the solid-to-liquid ratio of 1:20 to be stirred, and conducting suction filtration, washing and drying; repeating ammonia exchanging four times, afterwards, obtaining NH4-ZSM-34, and roasting NH4-ZSM-34 through air to obtain the H-ZSM-34 molecular sieve. The conversion rate of chloromethane in the reaction of using the H-ZSM-34 molecular sieve to prepare propylene through chloromethane is 87.0%,the selectivity sum of ethylene and propylene is 41.4%, the sum of the yields of ethylene and propylene is 36%, and the H-ZSM-34 molecular sieve does not get inactivated within 24 h. The preparing method has the advantages of being simple in technology, easy to operate and high in production efficiency.

Description

technical field [0001] The invention relates to the field of energy catalysis, in particular to a preparation method of H-ZSM-34 molecular sieve. Background technique [0002] Ethylene is a representative organic raw material for the development of petrochemical industry. It plays a leading role in petrochemical production and is mainly used for the production of polyethylene and ethylene oxide. Propylene can be used to produce important chemical products such as polypropylene, propylene oxide, acetone, isopropanol, phenol, glycerin, etc. It is an indispensable raw material for chemical production in modern social and economic development. At present, the production of ethylene and propylene mainly depends on oil. If the source of production can be transferred to natural gas, it will not only alleviate the oil crisis, but also meet the growing demand. [0003] At present, the production route of methyl halide to ethylene and propylene is mature, and molecular sieve catalyst...

AI Technical Summary

Problems solved by technology

[0003] At present, the production route of methyl halide to ethylene and propylene is mature, and molecular sieve catalyst is needed for the production of propylene from methyl halide. Although this method improves the yield of ethylene and propylene, due to the pore structure and acidity of the molecular sieve catalyst, it makes it difficult to It is easy to deactivate, so it is particularly important to prepare molecular sieve catalysts with long catalytic life, good stability and high catalytic performance