We have stadied the inhibitive properties of sodium chloride dihydrate precipitation and established a preventive method for caking at freezing temperature using these additives.
1) The solubility of sodium chloride decreased in proportion to the increase in concentration of the additives. This effect was significant since the hydration enthalpy also increased.
2) Sodium chloride dihydrate precipitates increased in proportion to the decrease in temperature. In particular, it showed a rapid rate of increase below -5°C.
3) Sodium chloride dihydrate precipitates decreased in proportion to the increase in concentration of the additives. This effect was significant since the hydration enthalpy also increased.
4) Caking at freezing temperature was prevented by the additives whose hydration enthalpy was greater than that of the sodium ion. This effect was significant since the hydration enthalpy also increased.