2024-07-05
Method for producing sodium hexametaphosphate by sodium chloride method
The invention provides a method for producing sodium hexametaphosphate by a sodium chloride method, which comprises that: according to the mol ratio of 1:1, sodium chloride and phosphoric acid are evenly mixed and subjected to melt polymerization at a temperature of between 650 and 700 DEG C for at least 30 minutes so as to completely remove chlorine hydride; and the product is subjected to quenching to be glassy so as to obtain the finished product of the sodium hexametaphosphate. In the method, the sodium chloride which is a low-priced and easily-bought raw material replaces sodium carbonate; moreover, the chlorine hydride is reclaimed so as to lower the production cost. The method has the advantages of short production flow, simple equipment, convenient operation and easy realization of industrialized production, and the P2O5 content in the sodium hexametaphosphate prepared by the method reaches more than 67.5 percent.