Improved apparatus and procedures for the measurement of solubility of rapidly equilibrating solid-liquid systems to 90 degrees C

An improved apparatus for measuring solubilities of solid-liquid systems at temperatures to 90 degrees C is described. The apparatus has a high capaci ty (up to 56 samples) and a long term temperature stability of +/-3 mK. The design allows the saturated solution to be multiply sampled and microfilte red at the equilibration temperature, making it particularly suited to rapi dly equilibrating systems. The reliability of the apparatus and sampling pr ocedures were tested by measuring the solubilities of NaCl, Na2SO4, and Na2 CO3 in water. The data obtained showed a routine precision of +/-0.05% rela tive and agreed to within +/-0.1% of recommended International Union of Pur e and Applied Chemistry values. (C) 1999 American Institute of Physics. [S0 034-6748(99)03602-3].