A METHOD FOR THE DETERMINATION OF WATER IN NONPOLAR LIQUIDS; THE SOLUBILITY OF WATER IN BENZENE

Abstract

A new method is described for the analysis of water in nonpolar organic liquids. It is based on an isotope dilution procedure and involves the exchange of the water present in the sample with D₂O. The change in isotopic composition of the D₂O is determined by infrared difference spectroscopy. The method appears to be accurate to ± 0.8%.The principal advantage of this method is that the difficult problem of calibration with organic–water standards is avoided. It is restricted, however, to solvents which have a low solubility in water and do not have exchangeable hydrogens.A series of solubility measurements were carried out for H₂O in C₆H₆ from 10 to 60 °C. The data were fitted to the usual interpolation equation In (f/x) = −A/T + B ln T + C, and the thermodynamic functions of solution, ΔG, ΔH, ΔC_P, and ΔS, were computed for the transfer of 1 mole of water from the benzene phase to the vapor phase.