Preparation method of Trisodium citrate dihydrate

According to the different raw materials, the preparation methods of Trisodium citrate dihydrate are as follows:
1, citric acid + sodium hydroxide method
The citric acid is dissolved in water, added to the sodium hydroxide solution, and a neutralization reaction occurs to generate a large amount of heat, which is treated by filtration, concentration, crystallization and the like to obtain a Trisodium citrate dihydrate. The method has simple process and good product purity; the disadvantage is that the finished product is high. It is currently only used to prepare laboratory supplies.
2, citric acid + soda ash method
The neutralization method improves the process, and the soda ash as a raw material is easy to purchase and has the advantage of low production cost; it is a production method generally adopted by various industrial enterprises.
3, citric acid + baking soda
This method is an improved preparation method for the soda ash product which is not applicable to the pharmaceutical industry. The method adopts high-quality baking soda, is dissolved in water according to the calculated amount, neutralized with citric acid, and is processed by concentration and crystallization to prepare pharmaceutical grade Trisodium citrate dihydrate. It is characterized by mild reaction conditions, good product quality and good process operation. At present, this law is mainly used in some pharmaceutical factories.
4, calcium citrate + soda ash method
The metathesis reaction is carried out by mixing calcium citrate with soda ash, and the insoluble matter is filtered to obtain Trisodium citrate dihydrate. The product has poor purity and long operating procedures. In the past few years, it has been reported that by adjusting the pH of the mixing conditions, the process flow is simplified, the production cost is reduced, and a better quality product is obtained.