Manufacturing method of dibutyl ester
I. Introduction
Dibutyl ester is a widely used raw material for the production of chemicals, which is mainly used in the industries of plastics, rubber, paints, inks and so on. With the continuous development of science and technology, the manufacturing method of dibutyl ester is also progressing.
II. Raw materials and formulations
The main raw materials for manufacturing dibutyl ester are butyric acid and ethanol. Among them, butyric acid can be n-butyric acid or isobutyric acid, and ethanol can be industrial grade ethanol. In addition, catalyst sulfuric acid and polymerization inhibitor hydroquinone are also needed.
The formula ratio is: butyric acid: ethanol: sulfuric acid: hydroquinone = 1:1.2:0.01:0.005 (mass ratio).
III. Manufacturing process
1. Esterification reaction
Butanoic acid and ethanol are added into the esterification reactor according to the formula ratio, sulfuric acid is added as a catalyst, and the reaction is heated to reflux temperature for esterification. The water generated by the reaction should be removed in time during the reaction to promote the reaction towards the generation of dibutyl ester. The reaction time is about 4-6 hours.
2. Neutralization and washing
After the reaction is completed, the reaction solution is cooled to room temperature, the remaining sulfuric acid is neutralized by the addition of sodium carbonate solution, and then washed with water until neutral.
3. Distillation
The washed dibutyl ester solution is distilled, the first atmospheric distillation to recover ethanol, and then distilled under reduced pressure to obtain pure dibutyl ester.
4. Precautions
1. The amount of catalyst sulfuric acid should be appropriate, too much will lead to equipment corrosion, too little will affect the esterification reaction.
2. The dosage of polymerizer hydroquinone should also be appropriate, too much will affect the product quality, too little will not effectively inhibit the polymerization reaction.
3. In the process of esterification reaction, the water generated by the reaction should be removed in time to promote the reaction in the direction of generating dibutyl ester.
4. In the process of distillation, the temperature and vacuum should be controlled to ensure the quality and yield of the product.
V. Product quality and yield
Using the above manufacturing method, a dibutyl ester product with high purity can be obtained, and the quality meets the national standard. The yield is generally above 90%.
VI.Three-waste treatment and environmental protection
In the manufacturing process of dibutyl ester, some waste water, waste gas and waste residue will be produced. In order to protect the environment, these three wastes need to be treated effectively. Wastewater can be treated by biochemical treatment or chemical treatment and other methods, waste gas can be treated by absorption, combustion and other methods, and waste residue can be comprehensively utilized or safely landfilled. At the same time, it is necessary to follow the environmental protection regulations and strengthen the environmental protection management in the production process to ensure the environmental protection and sustainability of the production process.
VII.Conclusion
Dibutyl ester, as an important raw material for the production of chemicals, is widely used in plastics, rubber, paint, ink and other industries. In this paper, a feasible manufacturing method of dibutyl ester is introduced, which takes butyric acid and ethanol as raw materials, adopts sulfuric acid as catalyst and hydroquinone as polymerization blocking agent, and can obtain the dibutyl ester product with high purity after esterification reaction, neutralization and washing, distillation and other processes. In the production process, it is necessary to pay attention to the dosage of catalyst and polymerization blocker, remove the water generated by the reaction in time, and control the distillation temperature and vacuum degree to ensure the quality and yield of the product. At the same time, it is necessary to strengthen the environmental protection management and effectively treat the three wastes generated to ensure the environmental protection and sustainability of the production process.
