Sodium tripolyphosphate/STPP is a common chemical raw material. This article is mainly from the formation, characteristics and structure of STPP, to give you a real understanding of STPP.

Phosphate ion in STPP is composed of three PO₄ tetrahedrons in the form of type I, type II and hexahydrate. Chongqing Chuandong Chemical Group reminds that we must distinguish STPP from sodium trimetaphosphate. Sodium trimetaphosphate is a cyclic compound, which is composed of n PO₄ tetrahedrons combined by common oxygen atoms. It exists in the form of type I, II and III) STPP type I and type II. It is mainly determined by the different coordination of sodium ions. That is, all sodium ions in type II are surrounded by oxygen and some sodium ions in type I are surrounded by oxygen atoms. Type I and type II are called high temperature type and low temperature type respectively because of their difference in heat release in water.

STPP is mainly made of phosphoric acid and soda or caustic soda. At present, in order to save cost and reduce investment, a large number of phosphate manufacturers are using wet-process phosphoric acid and 30% liquid caustic soda as raw materials, and need to cooperate with the process conditions - separation and purification to make the products meet the standards. Because the production process can achieve different conditions, the use of raw materials impurity content difference (for example: from cost savings considerations, some use wet-process phosphoric acid, some use thermal phosphoric acid to focus on quality). So there are obvious reasons for the quality gap of STPP produced by different manufacturers under the same standard in the STPP market.

Sodium tripolyphosphate/STPP produced by Chongqing Chuandong Chemical Group is made from thermal-process raw materials with high purity, less impurities and stable quality.