Manufacturing Method of Decanoic Acid
Decanoic acid is an important raw material for the production of chemicals, which is widely used in the fields of pharmaceuticals, pesticides, plastics, spices and so on. In this paper, we will introduce the manufacturing method of decanoic acid, including the steps of raw material preparation, reaction process and post-processing, and discuss the precautions and safety issues in its manufacturing process.
I. Raw material preparation
The main raw materials for manufacturing decanoic acid are n-decanol and carboxylic acid. The n-decanol can be made by paraffin cracking and fatty acid esterification, etc. The carboxylic acid can use common fatty acids such as acetic acid and propionic acid.
II. Reaction process
1. Esterification reaction
Add n-decanol and carboxylic acid into the reaction kettle according to a certain molar ratio, add appropriate amount of catalyst, such as sulfuric acid or hydrochloric acid, and heat and stir to carry out the esterification reaction. Temperature, acidity and alcohol-acid molar ratio should be controlled during the reaction to ensure the esterification reaction and the purity of the product.
2. Hydrolysis reaction
After completion of the esterification reaction, the reaction solution is cooled to room temperature, and an appropriate amount of aqueous alkali solution is added to carry out the hydrolysis reaction to produce decanoic acid sodium salt. The pH and temperature should be controlled during the hydrolysis reaction to avoid excessive hydrolysis and generation of by-products.
3. Acidification and crystallization
After the hydrolysis reaction is completed, the decanoic acid sodium salt solution is adjusted to pH 2-3 with acid, so that the decanoic acid is precipitated in the form of crystals. Temperature and stirring speed should be controlled during the crystallization process to promote the generation and purification of crystals.
III. Post-treatment
After the crystallization is completed, centrifugal separation, washing, drying and other post-treatment steps are carried out to obtain the decanoic acid product with higher purity.
IV. Precautions and safety issues
1. During the manufacturing process, operating procedures and safety regulations should be strictly observed to avoid safety accidents caused by improper operation.
2. The catalyst sulfuric acid or hydrochloric acid used in the esterification reaction is corrosive, attention should be paid to the anticorrosion of the equipment and the protection of the operators.
3. The aqueous solution of alkali used in hydrolysis reaction is alkaline, attention should be paid to control the pH value to avoid corrosion of equipment and injury to personnel.
4. In the process of crystallization, attention should be paid to controlling the temperature and stirring speed to avoid uneven crystallization or too fine crystallization affecting product quality.
5. In the post-treatment process such as centrifugal separation, washing and drying, attention should be paid to controlling the operating conditions to avoid the drop of product quality due to improper operation.
In short, the manufacturing process of decanoic acid needs to strictly abide by the operating procedures and safety regulations, and control each process parameter to ensure product quality and production safety. Meanwhile, the waste and by-products that may appear in the production process should be reasonably treated and utilized to avoid the waste of environment and resources.
