Purification method of ethyl acetate

Abstract

The invention relates to a purification method of ethyl acetate. The method comprises the following step: the ethyl acetate product is purified from ethyl acetate-ethanol-water mixture. The equipment of the method at least contains an ethyl acetate rectifying tower, an ethyl acetate recovery tower, an ethanol recovery tower and the associated equipment. The purification method is as follows: heat integration is realized between the ethyl acetate rectifying tower and the ethyl acetate recovery tower; the ethyl acetate product is obtained from the bottom of the ethyl acetate rectifying tower, wherein the ethyl acetate recovery tower uses water as extracting agent to perform extractive distillation operation; ethyl acetate is recycled from the tower top; ethanol-water mixture is discharged from the tower bottom and sent to the ethanol recovery tower; and ethanol-water mixture is obtained from the bottom of the ethanol recovery tower, a part of wastewater in the tower bottom is recycled, and the other part is discharged from the equipment. The operational energy consumption can be greatly reduced by adopting heat exchange and energy saving methods in the system. By adopting the method of the invention, the operational energy consumption can be reduced to 0.55 ton of steam for 1 ton of the ethyl acetate product, which can be reduced by more than 50% compared with the existing ethyl acetate refining method; the reaction process of returning ethyl acetate is not required, than the reaction process energy consumption can be reduced by more than 30%.

Description

technical field [0001] The invention relates to a method for purifying ethyl acetate, which is an energy-saving process for producing ethyl acetate from crude ester raw materials (mixture of ethyl acetate-ethanol-water) through a rectification process. Background technique [0002] Currently widely used ethyl acetate refining method ( figure 1 ) is to take the reaction crude ester (the mixture of ethyl acetate-ethanol-water) as raw material, and the oil phase after the reaction crude ester is left to stand for phase separation enters the ethyl acetate refining tower, and the refining tower still obtains the ethyl acetate product. A mixture of ethyl acetate-ethanol-water is extracted from the top of the refining tower. After cooling and phase separation, part of the oil phase is returned to the top of the refining tower as reflux, and the other part is recovered as head oil and returned to the esterification reaction process. The aqueous phase obtained by phase separation en...

AI Technical Summary

Problems solved by technology

Its biggest defect is that a large amount of ethyl acetate (accounting for about 50% of the ethyl acetate amount in the refining tower still) circulates between the refining tower and the reaction process; secondly, the primary yield of ethyl acetate in the above-mentioned method is low, and the operation energy consumption is high

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