Production process of hydroxyethyl cellulose hydroxyethyl cellulose HEC Hydroxyethyl cellulose (HEC) is a widely used cellulose ether, which has the characteristics of thickening, suspension, bonding, emulsifying, film-forming, moisture protection, antistatic, etc., and is widely used in various fields such as petroleum, medicine, food, cosmetics, etc. This article will detail the industrial production process of hydroxyethylcellulose.
1. Preparation of raw materials
The production of hydroxyethyl cellulose requires high-quality natural cellulose as raw material, commonly used in cotton, wood, etc. Before production, the raw materials need to be screened, dried, crushed and other pre-treatment for subsequent processing.
2. Alkalization
The pretreated natural cellulose is put into the reactor, sodium hydroxide solution is added, and alkalization is carried out at a certain temperature. The alkalinization process can break the crystal structure of cellulose, making it easy for subsequent etherification reactions.
3. Etherification reaction
Ethylene oxide is added to the cellulose after alkalization treatment, and the etherification reaction is carried out under the action of a catalyst. Etherification is a critical step in the production of hydroxyethyl cellulose, the purpose of which is to introduce ether bonds on the hydroxyl group of cellulose to produce hydroxyethyl cellulose.
4. Washing and separation
After the etherification reaction is completed, impurities such as unreacted ethylene oxide and sodium hydroxide, as well as catalysts, need to be separated from the product. This step is usually done by washing with water to remove any remaining chemicals.
5. Drying and crushing
After the impurities are separated, the hydroxyethyl cellulose needs to be dried and pulverized for subsequent packaging and use. Drying can be done by natural drying or oven drying, while crushing is by mechanical grinding to crush hydroxyethyl cellulose into fine powder.
6. Packaging and storage
Finally, the dried and pulverized hydroxyethyl cellulose is packaged and stored. Packaging is usually in a well-sealed plastic bag or foil bag to prevent hydroxyethylcellulose from getting wet or contaminated. Care needs to be taken to keep it dry and ventilated when storing, and avoid direct sunlight and high temperatures.
Through the above six steps, the industrial production of hydroxyethyl cellulose can be completed. As an important cellulose ether, hydroxyethyl cellulose has a wide range of application prospects and market prospects. With the continuous development of science and technology, the synthesis technology of hydroxyethyl cellulose will continue to improve and perfect, bringing more convenience and benefits to human production and life.