New technology for separating isopropanol-isopropyl ether azeotrope by using ionic liquids

Abstract

The invention relates to a rectification separation method, and concretely relates to a new technology for separating isopropanol-isopropyl ether azeotrope by using ionic liquids. The new ionic liquids [emim]<+>[BF4]<-> and [bmim]<+>[BF4]<-> (with the structures shown in figure 1) are adopted in the invention as extractants, and the isopropanol-isopropyl ether azeotrope is separated through adotpign a continuous rectification method. Rectifying towers adopted in the technology comprise an extraction rectifying tower, a solvent recovery tower and other auxiliary devices. The technology comprises the following steps: adding the isopropanol-isopropyl ether azeotrope into the central portion of the extraction rectifying tower, recovering the ionic liquids in the solvent recovery tower, pumping the ionic liquids into the extraction rectifying tower through using a pump in order to realize cycle use, and controlling different temperatures and reflux ratios of the above two towers in order to realize continuous production. The technology breaks use of a traditional solvent glycol as an extractant, improves the relative volatility of isopropanol-isopropyl ether, avoids the problem of poor solubility of traditional glycol as the extractant, and has the advantages of convenient operation, large operation elasticity and continuous production.

Description

technical field [0001] The invention relates to a new process for separating isopropanol-isopropyl ether azeotropic mixture by using ionic liquid, which belongs to the separation technology of isopropanol-isopropyl ether azeotropic mixture. Background technique [0002] Isopropyl alcohol (IPA) is one of the earliest petrochemical products produced in the world. It is mainly used for the production of acetone and as a solvent. There is a side reaction in the production process of isopropyl alcohol to produce isopropyl ether, and isopropyl ether (IPE) It is an important industrial solvent and organic raw material, which is mainly used in medicine, tobacco, environmental protection and chemical industries. Because it has a higher boiling point than common organic solvents such as ether and acetone, it is more beneficial to use isopropyl ether in some extraction operations. In addition to being used as a solvent for grease, wax, mineral oil, some natural resins, and ethyl cellu...

AI Technical Summary

Problems solved by technology

[0003] There are many studies on this azeotrope in many documents, such as using ethylene glycol as the extractant, but the solubility of the extractant in the azeotropic species cannot be ignored, resulting in a large amount of extractant and difficult to handle; Patent No. CN103044215A adopts ethylene glycol methyl ether to carry out intermittent rectification as extractant, but this method is applicable to intermittent operation and is unfavorable for large-scale industrial production; Due to the pre-heading treatment, it has the disadvantages of low yield and low economic benefit.

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