Phase Equilibria in Water-Salt Systems Containing Sodium and Calcium Chlorides and Urea at Temperatures below 0°C

Phase equilibria are studied in sections of the systems NaCl-CO(NH2)(2)-H2O, CaCl2-CO(NH2)(2)-H2O, and NaCl-CaCl2-CO(NH2)(2)-H2O at temperatures from 0 to -57 degrees C. The features of the mutual influence of the components on the temperatures of the eutectics in the systems and on the deicing ability of urea-salt mixtures are determined. It is found that the introduction of urea into the systems CaCl2-H2O and NaCl-CaCl2-H2O gives rise to low-temperature eutectics with crystallization temperatures of -54 and -57 degrees C, which are promising for the development of low-temperature deicing agents on their basis.