Purification method for ethyl acetate

Abstract

The present invention discloses a purification method for ethyl acetate. The purification method comprises the following steps of: (1) at least using an extraction column A, an ethyl acetate distillation column B, an extractant recovery column C and and a 95% ethanol recovery column D; (2) discharging an ethyl acetate solution layer from the top of the extraction column, and an extractant layer from at the bottom of the extraction column; (3) discharging an ethyl acetate layer from at the top of the ethyl acetate distillation column B, and the mixture of the extractant, a small amount of ethanol and water from the bottom of the ethyl acetate distillation column B; (4) discharging an extractant layer from the bottom of the the extractant recovery column C, and the mixture of acetic acid, water and ethyl acetate coming out from the top portion of the extractant recovery column C; and further discharging a ternary azeotrope of ethyl acetate, water and ethanol from the top of the 95% ethanol recovery column, 95% ethanol from the middle lower part of the the 95% ethanol recovery column, and water from the bottom of the 95% ethanol recovery column. The purification method disclosed by the present invention is high in purification and separation efficiency of the ethyl acetate and good in separation effect.

Description

technical field [0001] The invention relates to the field of chemical industry, in particular to a method for purifying ethyl acetate. Background technique [0002] Ethyl acetate is an important chemical raw material, which is widely used in perfumery, medicine and paint industry. In the industrial process of producing ethyl acetate, as production methods such as ethanol and acetic acid direct esterification method, ethanol catalytic oxidation method or catalytic denitrification method, all relate to water, alcohol and ethyl acetate separation, separation method in the prior art Generally, the feature that ethyl acetate itself forms a ternary azeotrope with water and ethanol is used. After the ternary azeotrope vapor is cooled, it is divided into two phases in the phase separator. The light phase is the ester phase, which is rich in ethyl acetate. , containing a small amount of ethanol and water. The heavy phase is the water phase, which is rich in water, secondly contains...

AI Technical Summary

Problems solved by technology

The advantage of this method is that the product ethyl acetate itself is used as a constant boiling agent. The disadvantage is that the ester phase in the normal temperature and pressure stratifier has a lot of water content, and its water carrying capacity as the reflux liquid is poor, so a large reflux ratio needs to be maintained. (R=4), so the amount of ester phase sent to the dehydration tower to produce ethyl acetate is not large, which limits the output

In addition, the water content of the ester phase sent to the esterification tower and dehydration tower is high, so the energy consumption is relatively large

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