Composite ionic liquid catalyst, and preparation method and application thereof

Abstract

The invention relates to a preparation method of a composite ionic liquid catalyst, and the prepared catalyst and application of the catalyst. The method comprises the following steps: 1) under the protection of dry inert gas, slowly adding metal halide into alkyl halogenated amine in batches, stirring for 10-50 minutes at room temperature, when part of the solid is converted into liquid with relatively strong fluidity, heating to 50-100 DEG C, and continuously stirring and reacting until all the solid is completely converted into uniform liquid A; and 2) adding nitrate into the liquid A, and continuously stirring to react for 6-12 hours to obtain the composite ionic liquid catalyst. The catalyst system prepared by the invention can greatly reduce the sensitivity of an ionic liquid catalyst to CO in the prior art, alkylation reaction can be directly carried out without separating mixed olefin, the total amount of target products ethylbenzene and / or isopropyl benzene and / or tert-butylbenzene accounts for 95% or above of the total molar weight of the product, byproducts are low, the raw material utilization rate is high, and the overall economic benefit is greatly improved.

Description

technical field [0001] The invention relates to the fields of chemical engineering and catalysts, in particular to a composite ionic liquid catalyst, its preparation method and application, especially for the alkylation reaction directly carried out by mixing olefins and benzene. Background technique [0002] Ethylbenzene, cumene and tert-butylbenzene are widely used chemical raw materials. Ethylbenzene is mainly used in the industry to produce styrene, and styrene can be used to produce plastics, synthetic rubber, synthetic resin and other downstream products with huge demand, so the demand for ethylbenzene at home and abroad is very huge. The main use of cumene is to synthesize phenol and acetone, and tert-butylbenzene is widely used in the synthesis of fine chemical products and their homologs, and is an important fine chemical intermediate in medicine, spices and pesticides. [0003] At present, the industry mainly produces ethylbenzene and cumene through the alkylation...

AI Technical Summary

Problems solved by technology

[0005] At present, there are many literatures and patents on the alkylation of benzene with monoolefins, but there are relatively few literatures and patents on the alkylation of benzene with mixed olefins

[0006] CN106694033A discloses a catalyst for the alkylation reaction of benzene and propylene. The catalyst is made of H-β, ZSM-5, vanadyl sulfate and binder. The yield of cumene can reach 96%, but the preparation process is complex and difficult industrialization

[0007] CN105665004A invented a molecular sieve with MFI topological structure, which is used to solve the problems of high xylene content and poor selectivity in molecular sieves used in the existing dilute ethylene and benzene alkylation technology. The ethyl selectivity of this molecular sieve can reach 99% % above, but it does not disclose the conversion of ethylene

[0008] CN105983439A compounded β-MCM-49 by chemical method in a certain proportion to prepare the β-MCM-41 composite molecular sieve which has the pore structure of MCM-49 molecular sieve and strong acidity of β molecular sieve, and applied the molecular sieve to benzene and In the ethylene / propylene alkylation reaction, the conversion rates of ethylene and propylene are both over 99%, and the selectivity of ethylbenzene and cumene is over 90%, but the amount of catalyst used in the reaction is very large, the operating conditions are complicated, and the reaction pressure high

Moreover, impurities such as carbon dioxide often exist in mixed olefins, and traditional chloroaluminate ionic liquids are sensitive to carbon monoxide, and acylation reactions between carbon monoxide and aromatics will occur. Therefore, an ionic liquid suitable for the alkylation of mixed olefins and benzene is provided. Catalysts become an urgent technical problem

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