Effects of pressure and temperature on the solubility of ammonium chloride in water

Solubility of ammonium chloride in water was measured at pressures in the range of 0.10-300MPa and temperatures in the range of 273.4-313.2K and was found to decrease with increasing pressure at each temperature and to increase with increasing temperature. Compression of the aqueous solution of ammonium chloride was also measured in order to estimate the partial molar volume at high pressure. The high-pressure solubility was then estimated thermodynamically. The estimated solubility agreed well with that measured directly, suggesting that the high-pressure solubility in the present work is thermodynamically verifiable.