Method and device for synthesizing ethyl lactate by using vapor permeation dehydration technology

Abstract

The invention relates to a method and a device for synthesizing ethyl lactate by using a vapor permeation technology and belongs to the technical fields of pervaporation membrane separation application and organic compound synthesis. The method comprises the following steps: performing reduced pressure distillation on lactic acid in a reaction kettle, and removing partial moisture in the lactic acid; adding ethyl alcohol and a catalyst according to a certain ratio, heating to a certain temperature, and enabling the reactants to mainly produce ethyl lactate and water under the catalytic action of the catalyst; performing heat transfer and mass transfer on rising vapor and descending reflux in the reaction kettle in the reaction process, distilling off the ethyl alcohol and water from the top of a rectifying column, and dehydrating by taking the distillate as a vapor permeation membrane dehydration material; carrying out distillate dehydration to obtain high-purity ethyl alcohol vapor, cooling and returning into the reaction kettle. According to the invention, the ethyl alcohol serves as a water-carrying agent, water carried in the raw materials and water produced in the reaction process can be continuously removed, the reaction is promoted to move to a direction of producing esters, the reaction conversion rate is improved, and the later water removal process is reduced.

Description

technical field

[0001] The invention relates to a method and a device for synthesizing ethyl lactate using steam permeation dehydration technology, and belongs to the technical field of pervaporation membrane separation application and organic compound synthesis. Background technique

[0002] Ethyl lactate is one of the important organic solvents, mainly used in spices and food. As a spice, the ester can be used to prepare rum, milk, butter, wine, fruit wine, coconut flavor essence, and used in food; it can also be used as a high-grade solvent for artificial pearls. At the same time, it is also the main organic solvent in the production of pesticides, and can also be used in coatings, inks and other fields. It is an environmentally friendly solvent with significant application prospects. In the production process, acid-catalyzed direct esterification is mainly used to produce ethyl lactate. This method directly reacts to reflux, and there is no dehydration process in the...

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