What methods and raw materials are used to produce excellent quality sodium tripolyphosphate/STPP?

 For many chemical raw materials, from raw materials to production processes are not unique, and some mature and commonly used production methods often have multiple. Sodium tripolyphosphate is an ordinary basic chemical raw material, and there are few opportunities for ordinary people to see directly in life. However, whether in industry or food, sodium tripolyphosphate plays a huge role. Today we will reveal the method and raw materials used to produce excellent quality sodium tripolyphosphate/STPP.

Many people in the chemical industry who understand sodium tripolyphosphate should know that its production process is actually very simple. It is precisely because of this simple production process that the quality of sodium tripolyphosphate is uneven, and there are many black-hearted vendors There is a phenomenon of adulteration.

The relatively mature production process for producing sodium tripolyphosphate/STPP mainly includes thermal method phosphoric acid method, wet method phosphoric acid method and wet heat combined method. For the first two are two different processes that are only the difference in the production process of phosphoric acid, and the combined production method of wet heat is relatively complicated, and can be subdivided into mixed acid method, mixed salt method, high temperature mixed acid method, high temperature mixed salt law.

And so many methods, the production method of thermal phosphoric acid method is currently an effective method for producing high-quality sodium tripolyphosphate. The advantages of the thermal phosphoric acid process are high quality, less impurities, more reliable technology, and reduced high energy consumption for concentration. Its production method is to first use phosphorus ore, silica and coke to reduce the phosphorus in the phosphate ore to elemental phosphorus, burn yellow phosphorus in the air to obtain phosphorus pentoxide, and then react the phosphorus pentoxide with water to obtain Phosphoric acid.

The subsequent production of sodium tripolyphosphate directly uses thermal phosphoric acid to react with soda ash or caustic soda to generate a neutralization solution (acid-base neutralization reaction). After the neutralization solution is fine-tuned (stoichiometrically), it can be used for The product is produced. And this process can also produce different sodium phosphate products (including disodium hydrogen phosphate, sodium dihydrogen phosphate, trisodium phosphate, etc.).

With the changes in the market for yellow phosphorus in 2021, the prices of caustic soda and phosphoric acid continue to rise. In order to save costs, many manufacturers switch to wet-process phosphoric acid and its by-product soda ash to produce sodium tripolyphosphate. But in ceramics, fire resistance, washing, products such as additives, food grade and other related high-demand industries simply cannot meet the requirements for use.

For the production of high-quality sodium tripolyphosphate, it is subdivided in the process and the adjustment of raw materials in the early stage. At present, Chongqing Chuandong Chemical Group has an independent phosphate mine and has always used thermal phosphoric acid to produce different grades of excellent quality sodium tripolyphosphate/STPP according to different industry uses.