Device and method for producing ethylene glycol diacetate by adopting dividing-wall reaction rectifying column

Abstract

The invention relates to a device and a method for producing ethylene glycol diacetate by adopting a dividing-wall reaction rectifying column. The device comprises a dividing-wall reaction rectifying column, a condenser, an acetic acid preheater, an ethylene glycol preheater, a layering device, a main column reboiler, an auxiliary column reboiler, a raw material acetic acid feeding pump, a raw material ethylene glycol and catalyst feeding pump, an oil phase reflux pump, a water phase feeding pump and a main column kettle fluid circulating pump; the ethylene glycol diacetate is produced by virtue of esterification reaction of ethylene glycol and acetic acid which are adopted as raw materials, and water generated in the esterification reaction is separated in the dividing-wall reaction rectifying column directly by virtue of co-boiling rectification, so that the water generated in the reaction is removed out of a reaction system in time, and the reactant acetic acid can be prevented from being removed out of the reaction system along with the water. The esterification, dehydration of acetic acid and recycling of entrainer are integrally performed in one column, so that not only can the reactant conversion rate and product yield be increased, but also the integration of the esterification and dehydration of acetic acid in the same column is realized, and the energy consumption and equipment investment can be effectively reduced.

Description

technical field [0001] The invention relates to the technical field of reactive rectification with dividing walls in the chemical field, in particular to a device and a method for producing ethylene glycol diacetate in a reactive rectification column with dividing walls. Background technique [0002] Ethylene glycol diacetate (EGDA) is a colorless and transparent liquid. It is an excellent, efficient, safe and non-toxic organic solvent. It is widely used in the manufacture of paints, adhesives and paint removers. It can also be used as a casting agent. Curing agent for resin, excellent solvent for various organic resins, especially nitrocellulose, and raw material for leather brightener. [0003] At present, the more commonly used method for preparing ethylene glycol diacetate is the direct esterification method of ethylene glycol and acetic acid. In the direct esterification method, the batch reaction or continuous fixed bed reaction is commonly used. Because the water gen...

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Problems solved by technology

Batch tank reaction or continuous fixed bed reaction is commonly used in the direct esterification method. Since the water generated by the esterification reaction cannot be removed in time, the forward reaction is limited, and the conversion rate of the reaction is low and the selectivity of the product is low. Low, high content of ethylene glycol monoacetate in the intermediate product, etc., which lead to problems such as complex refining process of subsequent products, and there is a problem of low production capacity

Although the conventional intermittent reaction distillation or continuous reaction distillation removes the water generated by the esterification reaction from the top of the tower while reacting, but because the relative volatility of acetic acid and water is close to 1, while removing the generated water, It also took away a large amount of reactant acetic acid, and there was also the problem that the conversion rate of the reaction and the product selectivity could not be significantly improved.

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