Manufacturing method of p-nitrochlorobenzene
I. Introduction
p-nitrochlorobenzene is an important raw material for the production of chemicals, which is widely used in the fields of dyestuffs, pharmaceuticals, pesticides and so on. In this paper, we will introduce the manufacturing method of p-nitrochlorobenzene, including raw material preparation, reaction process, post-treatment and so on.
Two, raw material preparation
The main raw materials for manufacturing p-nitrochlorobenzene are benzene, nitric acid and chlorine. Among them, benzene should be industrial grade purity, nitric acid should be used dilute nitric acid, chlorine should be industrial grade chlorine. Before feeding, the raw materials need to be inspected for quality to ensure that they meet the relevant standards.
III. Reaction process
1. Nitrification reaction
In the nitrification reactor, benzene is mixed with dilute nitric acid in a certain proportion, heated to a certain temperature, and the appropriate amount of catalyst is added to carry out the nitrification reaction. The nitrification reaction produces nitrobenzene and water. Temperature, acidity and amount of catalyst need to be controlled during the reaction to ensure the nitrification reaction and the quality of the products.
2. Chlorination reaction
Nitrobenzene is mixed with chlorine gas in a certain proportion, added to the chlorination reactor, heated to a certain temperature, and the chlorination reaction is carried out. The chlorination reaction produces p-nitrochlorobenzene and hydrogen chloride gas. It is necessary to control the temperature and flow of chlorine gas during the reaction to avoid the occurrence of side reactions.
IV. Post-treatment
1. Cooling and crystallization
The reaction solution is cooled to a certain temperature to precipitate p-nitrochlorobenzene crystals. The cooling process needs to control the cooling speed and temperature to avoid uneven crystallization or too fine crystallization.
2. Filtering and washing
The crystallized material is filtered to obtain p-nitrochlorobenzene crystals and mother liquor. Wash the crystals with appropriate amount of detergent to remove the impurities attached on the surface.
3. Drying and packaging
The washed p-nitrochlorobenzene crystals are dried and then packaged to obtain the final product.
V. Precautions
1. During the manufacturing process, safety operation procedures should be strictly observed to avoid fire, explosion and other accidents.
2. For the waste gas and waste water generated, they should be properly treated to avoid pollution to the environment.
VI.CONCLUSION
The manufacturing method of p-nitrochlorobenzene includes the steps of raw material preparation, nitration reaction, chlorination reaction and post-treatment. During the manufacturing process, each process parameter should be strictly controlled to ensure product quality and production safety. Meanwhile, the waste generated should be properly disposed of to protect the environment and ecological balance.
