Manufacturing method of diethyl carbonate
I. INTRODUCTION
Diethyl carbonate is an important organic chemical raw material, which is widely used in the fields of medicine, pesticide, plastics and spices. Therefore, it is of great significance to study the manufacturing method of diethyl carbonate to improve the production efficiency, reduce the cost and improve the product quality. In this paper, we will introduce the manufacturing methods of diethyl carbonate, including esterification method, carbonation method and ethanol method.
II, esterification method
Esterification method is one of the main methods to produce diethyl carbonate, the principle is to react ethanol and carbonic acid to produce diethyl carbonate and water. The specific steps are as follows:
1. Add ethanol and catalyst (such as sulfuric acid, phosphoric acid, etc.) to the reactor and heat to a certain temperature.
2. Carbon dioxide gas is introduced to react ethanol with carbonic acid to form diethyl carbonate and water.
3. The diethyl carbonate and water are separated by distillation to obtain a product of diethyl carbonate of high purity.
The advantages of the esterification method are simple process, convenient operation and low cost, but it is easy to produce by-products and requires strict control of the reaction conditions and the amount of catalyst.
Third, carbonation method
Carbonation method is the method of reacting ethanol and carbonate to generate diethyl carbonate and salt. Specific steps are as follows:
1. Add ethanol and carbonate (such as sodium carbonate, potassium carbonate, etc.) into the reaction kettle and heat to a certain temperature.
2. Carbon dioxide gas is introduced so that the carbonate reacts with carbon dioxide to form bicarbonate.
3. The bicarbonate reacts with ethanol to form diethyl carbonate and salt.
4. The diethyl carbonate and salt are separated by distillation to give a pure diethyl carbonate product.
The advantage of the carbonation method is that it can reduce the amount of catalyst used and improve the purity of the product, but the operation is more complicated and requires strict control of the reaction conditions.
Four, ethanol method
Ethanol method is the method of oxidizing ethanol into acetaldehyde, and then reacting with carbonate to generate diethyl carbonate. Specific steps are as follows:
1. Add ethanol to the reactor, pass oxygen for oxidation reaction, to produce acetaldehyde and water.
2. The resulting acetaldehyde is added to another reactor with a carbonate (e.g., sodium carbonate, potassium carbonate, etc.) and heated to a certain temperature.
3. The acetaldehyde reacts with the carbonate to form diethyl carbonate and salt.
4. The diethyl carbonate and salt are separated by distillation to give a pure diethyl carbonate product.
The advantage of the ethanol method is that it can avoid the use of catalyst and reduce the corrosion of equipment, but the reaction conditions are more demanding, requiring high temperature and high pressure conditions.
V. Conclusion
There are various methods for manufacturing diethyl carbonate, including esterification, carbonation and ethanol methods. Different methods have different advantages and disadvantages and scope of application, and the suitable manufacturing method should be selected according to the actual situation. Meanwhile, the reaction conditions and the quality of raw materials should be strictly controlled in the production process to improve product quality and production efficiency.
