Manufacturing Method of Ethyl Benzoate
Ethyl Benzoate is a colorless transparent liquid with fruity aroma, widely used in food, medicine, cosmetics and other fields. In the field of raw materials for chemical production, the manufacturing methods of Ethyl Benzoate mainly include esterification method, ester exchange method, reduction method and so on. This article will introduce the manufacturing method of esterification method in detail.
I. Esterification method
Esterification method is a commonly used manufacturing method of ethyl benzoate, the main raw materials are benzoic acid and ethanol. The reaction principle is that under the action of acid catalyst, benzoic acid and ethanol undergo esterification reaction to produce ethyl benzoate and water.
1. Process flow
The process flow of esterification method mainly includes the following steps: batching, esterification, distillation, cooling, fractionation and refining.
2. Operation points
(1) Ingredients: add benzoic acid and ethanol into the reactor according to a certain proportion, and add appropriate amount of acid catalyst at the same time.
(2) Esterification: At a certain temperature, carry out esterification reaction to produce ethyl benzoate and water.
(3) Distillation: the reaction solution is distilled to separate the unreacted ethanol and water.
(4) Cooling: the distilled ethyl benzoate is cooled to room temperature.
(5) Fractionation: the cooled ethyl benzoate is fractionated to obtain a product with higher purity.
(6) Refining: the ethyl benzoate after fractionation is refined to further improve the purity and quality of the product.
3. Precautions
(1) In the process of dosing, the proportion of raw materials and the amount of catalyst should be strictly controlled to ensure the smooth progress of the reaction.
(2) In the esterification reaction, appropriate temperature and stirring speed should be maintained to promote the reaction.
(3) During distillation, care should be taken to control the distillation temperature and pressure to avoid decomposition and loss of products.
(4) During cooling, the cooling rate should be controlled to avoid crystallization and delamination of the product.
(5) In the process of fractionation and refining, care should be taken to control the operating conditions in order to obtain products of higher purity.
II. Ester exchange method
Ester exchange method is a method to manufacture ethyl benzoate from methyl benzoate and ethanol. The reaction principle is that under the action of acid catalyst, methyl benzoate and ethanol undergo ester exchange reaction to produce ethyl benzoate and methanol. The method has the advantages of easy availability of raw materials and mild reaction conditions, but the yield is low.
1. Process flow
The process flow of ester exchange method mainly includes the following steps: batching, ester exchange, distillation, fractionation and refining.
2. Operation points
(1) Dosing: add methyl benzoate and ethanol into the reactor according to a certain proportion, and add appropriate amount of acid catalyst at the same time.
(2) Transesterification: Under a certain temperature, transesterification reaction is carried out to produce ethyl benzoate and methanol.
(3) Distillation: the reaction solution is distilled to separate the unreacted methyl benzoate and methanol.
(4) Fractionation: The distilled ethyl benzoate is fractionated to obtain a product of higher purity.
(5) Refining: carry out refining of ethyl benzoate after fractionation to further improve the purity and quality of the product.
3. Precautions
(1) In the process of dosing, the proportion of raw materials and the amount of catalyst should be strictly controlled to ensure the smooth progress of the reaction.
(2) In the transesterification reaction, appropriate temperature and stirring speed should be maintained to promote the reaction.
(3) During distillation, care should be taken to control the distillation temperature and pressure to avoid decomposition and loss of products.
(4) In the process of fractionation and refining, care should be taken to control the operating conditions in order to obtain products of higher purity.
Third, reduction method
Reduction method is a method of generating ethyl benzoate by reduction reaction using benzoic acid as raw material. This method has the advantages of single raw material and higher yield, but the operation is more complicated.
1. Process flow
The process flow of reduction method mainly includes the following steps: dosing, reduction, distillation, fractionation and refining.
2. Operation points
(1) Dosing: add benzoic acid into the reactor, meanwhile add appropriate amount of reducing agent and catalyst.
(2) Reduction: at a certain temperature, the reduction reaction is carried out to produce ethyl benzoate.
(3) Distillation: the reaction solution is distilled to separate the unreacted benzoic acid and the reducing agent.
(4) Fractionation: the distilled ethyl benzoate is fractionated to obtain a product of higher purity.
(5) Refining: carry out refining of ethyl benzoate after fractionation to further improve the purity and quality of the product.
3. Precautions
(1) In the process of dosing, the proportion of raw materials and the amount of catalyst should be strictly controlled to ensure the smooth progress of the reaction.
(2) In the reduction reaction, proper temperature and stirring speed should be maintained to promote the reaction. Attention should also be paid to controlling the dosage and addition rate of the reducing agent to avoid excessive reduction and generation of by-products.
(3) During distillation, care should be taken to control the distillation temperature and pressure to avoid decomposition and loss of products. Attention should also be paid to the collection of unreacted benzoic acid and reductant for recycling.
(4) During fractionation and refining, care should be taken to control the operating conditions in order to obtain products of higher purity. Attention should also be paid to the maintenance and upkeep of the equipment to ensure normal operation and service life.
