New energy-saving production process of ethyl acetate

Abstract

The invention relates to a new energy-saving production process of ethyl acetate. The process comprises the sections of esterification, light removal, refining and recovery, and the membrane separation section is added between the esterification section and the light removal section. The organic phase at the esterification tower top is subject to membrane separation to desorb most moisture, and one part of the treated organic phase returns to an esterification tower to reflow and the other part is sent to a light removal tower to be refined. The membrane separation section comprises a vacuum cover (with a membrane module inside), a condenser, a penetrating fluid tank, a buffer tank and a vacuum pump. The method provided by the invention can greatly reduce water circulating in the esterification and light removal sections, save the heating steam in the esterification tower and the light removal tower, reduce the loads of the esterification tower and the light removal tower and further improve the production capability of the esterification tower and the light removal tower.

Description

technical field [0001] The invention relates to a new energy-saving production process of ethyl acetate. Specifically, a membrane separation section is added between the esterification tower and the light removal tower. The organic phase at the top of the esterification tower undergoes membrane separation to remove most of the water, part of which is returned to the esterification tower for reflux, and part of which is sent to the light removal tower for refinement. Background technique [0002] Ethyl acetate is one of the most widely used fatty acid esters. It has excellent solubility and is a fast-drying industrial solvent. It is widely used in ethyl fiber, acetate fiber, chlorinated rubber, vinyl resin, acetate fiber Production of resin, synthetic rubber and other polymers and pharmaceutical intermediates; it can also be used to produce liquid nitrocellulose ink for copiers; it can be used as a freshener in the textile industry; it can be used as a flavor extractant for s...

AI Technical Summary

Problems solved by technology

Since ethyl acetate, ethanol and water can form a ternary azeotrope, any two components can also be azeotroped, and when producing ethyl acetate, the amount of water in the raw material and the water generated by the reaction is far greater than what can be taken away by the azeotropy of ester water Water, the organic phase at the top of the esterification tower needs to be refluxed to carry water, but the water content in the organic phase is relatively high, so the ability to reflux to carry water is poor. Usually the reflux ratio of the esterification tower must reach about 3 to 5; The water content in the crude ester of the light tower is relatively high. In order to increase the yield of ethyl acetate, while ensuring that the tower bottom is produced without water and ethanol, the reflux ratio at the top of the tower is usually above 7; in addition, the traditional process is to reduce The consumption of ethanol, the organic phase containing ethyl acetate, ethanol and water extracted from the top of the light removal tower returns to the still of the esterification tower to continue to participate in the reaction, causing a part of water to circulate in the esterification and light removal processes. The total consumption accounts for more than 4 / 5 of the energy consumption of the whole process, and the gas-liquid phase load of these two towers is relatively large, and the production capacity is also limited to a certain extent

[0004] In short, in the traditional process, due to a certain amount of water circulating in the system, the reflux ratio of the esterification tower and the light removal tower is large, resulting in high energy consumption and limited production capacity.

Images