Sobol' O. Generation of thiosulfate crystalline hydrates Na2S2O3·5H2O, sulphate Na2SO4·10H2O and salt cake Na2SO3·7H2O out of aqueous solutions and their properties

Object - crystalline hydrates: Nа2S2О3·5Н2О, Nа2SО4·10Н2О, Nа2SО3·7Н2О. The purpose - to determine the synthesis regularity of sodium salts hydrates from own crystallization water and from their water solutions, depending on history of a liquid phase. Methods: thermal (DSC,TGA, CTA, DTA), X-Ray difraction, optical microscopy, measuring of specific conductivity. The conditions of hydrates synthesis of sodium salts during transition from quasiequilibrium to no equilibrium-explosive crystallization are determined. The diagrams of binary crystalline hydrates with metastable regions are constructed and analyzed. The determined regions of synthesis of crystalline hydrates and their mixtures are recommended for creation of thermal accumulate materials (TAM) on the basis of phase transformations. Field of application: heat-and-power engineering.