As the application of carboxymethyl cellulose (CMC China chemical) continues to expand, the preparation methods of CMC China chemical are also constantly studied, which is an important part of the chemical industry in China. At present, traditional chemical methods are widely used to prepare carboxymethyl cellulose. Usually, there are two production methods: water method and solvent method.
Production Technology of Water Medium Method
It is a method to make CMC China chemical by reacting alkali cellulose with etherification agent in the presence of free alkali and water.
Its characteristics are simple equipment, low investment, low cost, uneven product quality, low ether efficiency and low viscosity of the product.
2.The production process of the solvent method
The medium method, also known as an organic solvent method, is the process of making CMC China chemicalby alkalization and Etherification in the presence of organic solvent as a reaction medium. According to the amount of reaction diluent, it can be divided into a slurry method and kneading method (solvent method or suspension method).
Characteristics of the solvent method:
(1)Heat and mass transfer are rapid and uniform in the reaction process.
(2)The main reaction speed is fast, the side reaction is reduced, and the utilization ratio of the etherifying agent is 10-20% higher than that of the water medium method.
(3)The stability and homogeneity of the reaction are improved, and the substitution homogeneity and performance are greatly improved.
(4) With the use of a large number of organic solvents, the material consumption is increased, the investment of organic solvent separation and recovery equipment is increased, and the production cost is higher than that of water medium process.