Abstract
This article presents thermodynamic calculations of the interaction of zinc and iron chlorides with phosphoric acid. The influence of temperature and duration of the interaction on the degree of decomposition of metal chlorides is also determined. It is established that with increasing the temperature and the duration of interaction, the degree of conversion of zinc and iron chlorides to metal phosphates increases and the residual chlorine content in the product simultaneously decreases. The quality control of the obtained products was carried out using physical, chemical and crystal-optical methods of analysis.