Abstract: The isothermal solubilities of ternary systems HCl-MgCl₂-H₂O and LiCl-MgCl₂-H₂O at -10℃ have been determined. Three crystallization fields corresponding to MgCl₂·8H₂O, MgCl₂·6H₂O and HCl·MgCl₂·7H₂O and three crystallization fields corresponding to MgCl₂·8H₂O,MgCl₂·6H₂O and LiCl·2H₂O have been found for the first and second systems respectively.The existence of LiCl·MgCl₂·7H₂O and so called"2nd double salt"reported in[1]hasn't been found in this work.The salt-out rates of HCl and LiCl to MgCl₂ were compared.

Key words: hydrogen chloride, lithium chloride, magnesium chloride, phase equillibrium, isothermal solubility