Cyanoethyl ester is an important organic chemical raw material, which is widely used in the fields of medicine, pesticide, plastics and rubber. In this paper, we will introduce the manufacturing method of cyanoethyl ester, including raw material preparation, reaction process, post-treatment and precautions.
I. Raw material preparation
The main raw materials for manufacturing cyanoethyl ester are ethyl chloride, sodium cyanide and methanol. Among them, chloroethane can be produced by reacting ethylene with hydrogen chloride, sodium cyanide can be produced by reacting sodium hydroxide with hydrocyanic acid, and methanol can be produced by catalytic synthesis of synthesis gas (CO and H2).
II.Reaction process
The manufacturing process of cyanoethyl ester is a typical nucleophilic substitution reaction. The steps are as follows:
1. Add a fixed amount of methanol and sodium cyanide to the reactor, stir well, and then lower the temperature to 0-5℃.
2. Under the condition of stirring, slowly add ethyl chloride dropwise, and control the rate of dropwise acceleration so that the reaction temperature does not exceed 10℃.
3. After dropwise addition, continue stirring for 1-2 hours, then raise the temperature to reflux temperature and maintain reflux condition for 2-3 hours.
4. At the end of the reaction, cool down to room temperature, pour the reaction solution into a dispensing funnel and wash with water until neutral.
5. The organic phase was dried with anhydrous sodium sulfate and then distilled to recover methanol to obtain the crude cyanoethyl ester.
III. Post-treatment
The crude cyanoethyl ester needs to be refined to obtain a product with higher purity. The refining method can be adopted such as distillation or crystallization. Among them, distillation method is suitable for large-scale production, and crystallization method is suitable for small-scale production. The purity of cyanoethyl ester after refining can reach more than 99%.
4. Precautions
1. Raw materials used in the manufacturing process of cyanoethyl ester, ethyl chloride, sodium cyanide and methanol are all toxic to a certain extent, and require strict control of the operation process to avoid leakage and contact.
2. The temperature should be controlled during the reaction process to avoid the side reaction triggered by too high temperature.
3. The post-treatment process needs to pay attention to safety, avoiding contact with heat sources and open flames.
In conclusion, the manufacturing process of cyanoethyl ester requires strict control of operating conditions and raw material quality to ensure product quality and production safety. Meanwhile, the waste water and waste gas generated during the production process need to be properly treated to avoid harming the environment and human body.
