Theoretical Analysis of Integrated Processing of Sulfate Salts of Uzbekistan
Based on the data obtained from experimental studies, a volume diagram of the phase equilibria of the 2Na +, 2K +, Mg 2+ || SO4 2- 2C1 -H2O system at 0.25 and 75 ºС. The boundaries of the contact areas of salt crystallization are determined. Theoretical analysis of the 2K+, 2Na+, Mg2+ // 2Cl -, SO4 -2 -H2O system at 0 ºС showed that the volume fraction of shenite reaches more than 24%, and at 25 ºС the volume fraction of astrakhanite is 15%, and at 75 ºС the proportion of glaserite reaches more than 30%. Based on these data, 3 ways of processing sulfate salts in the presence of potassium chloride are recommended: - after separation of the insoluble phase and/or sodium chloride from a solution consisting of components of the 2Na+, Mg2+ // 2Cl-, SO4-2 -H2O system, synthesize astrakhanite; after separation of insoluble residue and/or sodium chloride, a calculated amount of potassium chloride is added to the clear solution, according to the stoichiometry of sodium sulfate at a temperature above 75 ºС and glaserite is determined; after the determination of insoluble residue and/or sodium chloride, from sulfate natural salts calculated amounts of potassium chloride are added to the system, according to the stoichiometry of magnesium sulfate at a temperature of about 0 ºС and schoenite is separated.