Ethyl acetate synthesis method utilizing membrane separation dehydration

Abstract

The invention discloses an ethyl acetate synthesis method utilizing membrane separation dehydration. Ethyl alcohol and acetic acid are reboiled and then enter an esterification kettle so as to carry out esterification reaction in the presence of a catalyst; a reaction product enters an esterification tower so as to be separated; a gas phase is distilled off from a tower top, condensed and layeredthrough a layering tank so as to extract ethyl acetate; the ethyl alcohol is vaporized by evaporation, then enters a raw material pervaporation permeable membrane assembly so as to be dehydrated, andis then fed into the esterification tower so as to be reacted with the acetic acid; crude ethyl acetate is vaporized by evaporation, then enters an esterification pervaporation permeable membrane assembly, and is then divided into two parts; one part reflows to the esterification tower so as to be used as a water-carrying agent, and the other part enters a refining tower so as to be refined, so that purified ethyl acetate is obtained. According to the ethyl acetate synthesis method utilizing membrane separation dehydration provided by the invention, a pervaporation membrane method is adopted for removing moisture of the raw material ethyl alcohol and a coarse ester on the top of the esterification tower without the limitation of azeotropy, no third component is introduced, the yield and the product purity are ensured, a craft process is simple, the continuous operation is realized, and the energy consumption is low.

Description

technical field [0001] The invention relates to a synthesis method of ethyl acetate, in particular to a synthesis method of ethyl acetate utilizing membrane separation and dehydration. Background technique [0002] Ethyl acetate is an important organic chemical raw material, which can be used to manufacture acetamide, acetoacetate, etc., and as an industrial solvent, it can be used in paint coatings, adhesives, ethyl cellulose, artificial leather, linoleum colorants, artificial fibers As a binder, it is used in the production of printing ink and artificial pearls; as an extractant, it is used in the production of medicines, organic acids and other products and is used in flavors and fragrances, medicines, advanced inks, collodion, nitrocellulose, Widely used in industries such as dyes. [0003] Esterification synthesis is the traditional production method of ethyl acetate. Under the catalysis of concentrated sulfuric acid, ethanol and acetic acid react in the esterification...

AI Technical Summary

Problems solved by technology

Because the water content (about 9wt.%) in the ethyl acetate-water-ethanol ternary azeotrope differs less from the partially miscible water content (about 5-6wt%) at normal temperature, the water-carrying ability of the reflux ester is relatively poor. The reflux of the esterification tower is relatively large, usually between 3-5, and the raw ethanol itself is 95% ethanol or other ethanol with a relatively large water content, and the water brought into the kettle is more, requiring more crude oil. ester reflux; moreover, the water content in the crude oil entering the refining tower is relatively high. In order to ensure that the product extracted from the tower still does not contain water and ethanol, the reflux of the crude ester at the top of the tower is also relatively high. In addition, in order to reduce the consumption of ethanol , the organic phase separated from the mixture containing ethyl acetate, ethanol and water withdrawn from the top of the refining tower returns to the still of the esterification tower to continue to participate in the reaction, resulting in a part of water circulating in the esterification tower and the refining tower, and the energy consumption is relatively high high

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