How acetonitrile is made

Acetonitrile is how to make?

Acetonitrile (CHYCN) is an important chemical raw material, which is widely used in medicine, agricultural chemicals, plastics, electronic products and other industries. How is acetonitrile made? Its production process mainly includes several steps from raw material selection, reaction process to product purification. This article will analyze the preparation of acetonitrile in detail to help you better understand the production process of this chemical.

Acetonitrile Raw Material Selection

The first step in how acetonitrile is made is the choice of raw materials. The common acetonitrile production method requires the use of ammonia (NH3) and ethylene (C₂ H₂) as the main raw materials. Ammonia is a simple source of nitrogen, while ethylene is an important petrochemical by-product. Through the reaction of these two raw materials, acetonitrile can be synthesized efficiently.

Ammonia and Ethylene Reaction

One of the production methods of acetonitrile is the "ammonia and ethylene cyanation reaction method". In this process, ammonia reacts with ethylene at high temperature and under the action of a catalyst to form acetonitrile. The reaction equation is:

[ C2H4 + NH3 \xrightarrow{\text {Catalyst}} CH3CN + H_2 ]

this reaction is usually carried out at high temperature (300-500°C) and high pressure, and requires the use of catalysts such as certain metal cyanides or aluminum alloys. The by-product in the reaction is primarily hydrogen (H₂). The advantages of this method are simple raw materials, high production efficiency, and suitable for large-scale industrial production.

Acetonitrile Purification

Another key step in how acetonitrile is made is the purification of the product. Although the reaction results in crude acetonitrile, it usually contains some impurities such as moisture, unreacted ethylene, ammonia, etc. In order to obtain high purity acetonitrile, it is necessary to remove these impurities by distillation and adsorption.

In industrial production, distillation is a common separation method. After the first step of distillation of the crude acetonitrile, high purity acetonitrile can be obtained, and impurities and by-products can be separated at the same time. This process is usually completed in multiple distillation columns, and acetonitrile with a purity of more than 99% can be obtained.

Other production methods

In addition to the reaction of ammonia and ethylene, there are other more complex production methods. For example, one method is to prepare acetonitrile by reaction of propylene with ammonia. This process is similar to the ammonia and ethylene reaction process, but the reaction feed is propylene instead of ethylene.

Acetonitrile can also be synthesized by the reaction of chloride and cyanide, which is less used because of the complexity of the process and the difficulty of handling the by-products.

Summary

From the above analysis, it can be seen how acetonitrile is made, mainly through the cyanation reaction of ammonia and ethylene, or some other alternative method. The whole production process includes the selection of raw materials, the control of the reaction process and the purification of products. The production process of acetonitrile has been optimized with the development of science and technology, making it an indispensable raw material in the modern chemical industry.