Method for manufacturing dioctyl adipate
I. INTRODUCTION
Dioctyl adipate (DOA for short) is a widely used raw material for the production of chemicals, which is mainly used for the production of plasticizers and lubricants. Due to its unique chemical properties, DOA has a wide range of applications in industries such as plastics, rubber, paints and coatings. In this paper, the manufacturing method of dioctyl adipate will be introduced in detail.
II. Materials and Equipment
1. Materials: adipic acid, octanol, catalyst (such as p-toluenesulfonic acid), antioxidants, etc.
2. Equipment: esterification reactor, distillation tower, condenser, stirrer, pump and so on.
3. Manufacturing steps
1. Esterification reaction
In the esterification reactor, adipic acid and octanol are added, as well as an appropriate amount of catalyst. Under the action of the stirrer, the materials are mixed thoroughly. Then the reactor is heated and the temperature is controlled at 120-150°C, so that the esterification reaction of adipic acid and octanol occurs to produce a mixture of dioctyl adipate and water.
2. Dehydration
After the esterification reaction, the reaction solution is transferred to a distillation column for dehydration operation. In the distillation column, appropriate temperature and vacuum are controlled so that water vapor is drawn out for dehydration purposes. During the dehydration process, the acid value and moisture of the liquid at the bottom of the tower need to be tested regularly to ensure product quality.
3. Refining
The solution of dioctyl adipate after dehydration contains unreacted adipic acid and octanol, which requires refining operation. Transfer the solution to another distillation column, control the appropriate temperature and vacuum, vaporize the unreacted adipic acid and octanol, and collect the dioctyl adipate product at the bottom of the column.
4. Add antioxidant
In order to improve the stability of the product, add appropriate amount of antioxidant to the refined dioctyl adipate and mix well.
4. Precautions
1. During the manufacturing process, parameters such as temperature, vacuum and stirring speed of each step should be strictly controlled to ensure product quality and yield.
2. The selection and dosage of catalyst have important influence on the rate and product selectivity of esterification reaction, so it needs to be optimized according to the actual situation.
3. In the process of dehydration and refining, the acid value, moisture and other related indexes of the product should be tested regularly to ensure that the product quality meets the standard.
V. Conclusion
Through the above steps, we can successfully manufacture dioctyl adipate. This manufacturing method has the advantages of easy operation and stable product quality, and is suitable for large-scale production. In the actual production process, the manufacturing parameters should be adjusted and optimized according to the specific conditions in order to improve the production efficiency and reduce energy consumption.
