Semi-automated apparatus for the determination of liquid solubilities: mutual solubilities of water and butan-2-ol
Abstract
A semi-automated apparatus for determining liquid–liquid solubilities by the traditional ‘synthetic’ method has been developed. The apparatus employs a programmable thermostat and a coherent (laser) light source coupled to a photodetector to detect accurately phase-transition temperatures. Cloud points and clear points obtained have a precision of ca.± 10 mK and are shown to be defined more readily and precisely than through visual observations. This system has been used to redetermine the mutual solubilities of highly pure butan-2-ol and water between 268 and 387 K at near atmospheric pressure. The unusual shape of the solubility curve previously reported for these two liquids at temperatures below 283 K is confirmed.