Manufacturing method of dioctyl phthalate (DOP)
Dioctyl phthalate (DOP) is a common plasticizer widely used in plastics, rubber, paints, coatings and other fields. This article will introduce the manufacturing method of DOP.
I. Raw material preparation
The following raw materials are needed for the manufacture of DOP: phthalic anhydride, octanol.
II.Reaction Principle
DOP is manufactured by the esterification reaction between phthalic anhydride and octanol to produce dioctyl phthalate and water.
III. Process Flow
1. Add phthalic anhydride and octanol into the reaction kettle according to a certain ratio, heat up to a certain temperature, and start the esterification reaction.
2. During the reaction, catalyst needs to be added in time to promote the reaction. At the same time, the water generated by the reaction needs to be removed continuously to keep the reaction going.
3. When the reaction is complete, the heating is stopped, the reaction solution is cooled to room temperature, and then left to stratify.
4. After layering, the upper liquid layer was poured out to obtain the crude DOP product. The crude DOP product contains unreacted feedstock, catalyst and other impurities, which require further treatment.
5. The crude DOP product is subjected to refining treatment, usually by distillation, washing and other methods, in order to remove impurities and obtain pure DOP product.
4. Precautions
1. During the production process, the temperature and time of the reaction need to be strictly controlled to ensure that the reaction is carried out completely.
2. It is necessary to test the quality indexes of the product regularly, such as acid value, color, moisture, etc., to ensure the quality and stability of the product.
3. During the production process, safety needs to be taken care of to avoid fire, explosion and other accidents.
All in all, the manufacture of DOP needs to master certain chemical technology and operation methods, and also needs to strictly control the production process to ensure the quality and safety of the products.
