Ethylene Glycol Diacetate (EGDA) is an important raw material for the production of chemicals, which is widely used in the fields of plastics, fibers, coatings and inks. This article will introduce the manufacturing method of ethylene glycol diacetate, including the steps of esterification reaction, refining and purification.
I. Esterification reaction
The manufacture of ethylene glycol diacetate is mainly realized by esterification reaction. Esterification reaction refers to the reaction between acid and alcohol to produce ester and water under certain conditions. In this reaction, ethylene glycol reacts with acetic acid under certain conditions to form ethylene glycol diacetate and water.
The reaction equation of esterification reaction is as follows:
CH3COOH + HOCH2CH2OH → CH3COOCH2CH2OOCCH3 + H2O
In actual production, esterification reaction is usually carried out with acidic catalysts, such as sulfuric acid and phosphoric acid, in order to promote the reaction. Meanwhile, in order to remove the water generated by the reaction in time, water-carrying agents, such as benzene and toluene, are required to separate the water from the reaction system. Factors such as temperature, pressure and catalyst dosage of the
esterification reaction have an important influence on the progress of the reaction and the quality of the product. Therefore, it needs to be optimized and adjusted according to the specific situation in the actual production. Refining and purification
The crude product of ethylene glycol diacetate obtained from esterification reaction contains unreacted raw materials, by-products, catalysts and other impurities, which need to be refined and purified to obtain high-quality ethylene glycol diacetate products. The methods of
refining and purifying include distillation, crystallization, adsorption, etc.. Among them, distillation is a common method for the purification of ethylene glycol diacetate. Through distillation, ethylene glycol diacetate can be separated from unreacted raw materials, by-products, and so on, to obtain ethylene glycol diacetate products with higher purity.
When carrying out distillation purification, it is necessary to select the appropriate distillation temperature and pressure and other conditions according to the boiling point of ethylene glycol diacetate and the nature of impurities, in order to ensure the quality and yield of the product.
3. Precautions for production operation
In the production process of ethylene glycol diacetate, the following matters need to be paid attention to:
1. Strictly control the reaction temperature and pressure to avoid side reactions and safety problems during the reaction.
2. Select suitable catalyst and water-carrying agent to improve the rate and selectivity of the reaction.
3. During the refining and purification process, it is necessary to ensure the cleanliness and sealing of the equipment to avoid contamination and loss of products.
4. Regular inspection and maintenance of the production equipment is required to ensure normal operation and service life of the equipment.
All in all, the manufacture of ethylene glycol diacetate needs to go through the steps of esterification reaction and refining and purification, and it needs to strictly control the conditions of the production process and operation precautions to ensure the quality and yield of the product.
