Manufacturing method of diphenyl phosphite
Diphenyl phosphite is an important organophosphorus compound, widely used in pesticides, pharmaceuticals, plastics, dyes and other fields. In this article, we will introduce the manufacturing method of diphenyl phosphite, including raw material preparation, reaction process, and post-treatment.
I. Raw material preparation
The main raw materials for manufacturing diphenyl phosphite are phenol and phosphite. In order to ensure the smooth progress of the reaction, it is necessary to first add phenol and phosphite to the reaction kettle at a certain molar ratio. At the same time, a certain catalyst needs to be added to promote the reaction. Commonly used catalysts are sulfuric acid and phosphoric acid.
II. Reaction process
In the reaction kettle, phenol and phosphite under the action of catalyst undergo esterification reaction to produce diphenyl phosphite and water. The reaction process needs to control a certain temperature and pressure to ensure the smooth progress of the reaction. At the same time, the reactants need to be stirred continuously to promote the uniformity of the reaction.
Third, post-treatment
After the reaction is finished, the reaction product needs to be post-treated. First, the reaction solution needs to be cooled to room temperature, and then a certain amount of alkaline absorbent is added to neutralize the acid produced during the reaction. Commonly used alkaline absorbents include sodium hydroxide and potassium hydroxide.
Next, the reaction solution needs to be separated and purified. Commonly used methods include distillation, extraction, and crystallization. Through separation and purification, diphenyl phosphite products with higher purity can be obtained.
IV. Precautions
In the process of manufacturing diphenyl phosphite, the following matters need to be noted:
1. control the reaction temperature and pressure to avoid overheating or overpressure;
2. choose a suitable catalyst to ensure the smooth progress of the reaction;
3. in the post-treatment process, attention needs to be paid to the dosage of alkaline absorbent and the degree of neutralization to avoid the impact on the purity of the product;
4. In the process of separation and purification, it is necessary to choose suitable methods and equipment according to the nature of the product and the actual situation, in order to ensure the purity and yield of the product.
In conclusion, the manufacturing method of diphenyl phosphite needs to control the process parameters and operation points of each link to ensure the quality and yield of the product. At the same time, it is necessary to pay attention to safety and environmental protection during the production process and comply with relevant laws, regulations and standard requirements to ensure the legality and sustainability of production.
