Phase Diagram of NaClO-NaCl-H₂O System

Abstract

Studies were made on the phase diagrams of NaCl0-NaCl-H₂0 system at 0, 5, 10°C. The mixture of H₂0, NaClo-. H₂0, and NaCl was stirred at least 2 hours in a thermostat; then a saturated solution was obtained. This mixture was settled for 3 hours in the thermostat, then the solution and wet crystals were analyzed respectively.
The amount of Cl0- was determined by iodometry and the total amount of Cl was determined by Mohr's method after Cl0- was decomposed to Cl- by the addition of H₂O^2-. Then the amount of Cl- in the original saturated solution was calculated by the following equation: Total Cl- Cl0-.
NaCl0-. H₂O and NaCl were stable at these temperatures, and no solid solution between these compounds was found. It was found that the mole fraction of Cl0- in the eutectic composition increased as the temperature raised.