PHASE-BEHAVIOR OF 1-ALKANOL + ALKANE MIXTURES - GAS-LIQUID CRITICAL-TEMPERATURES

The gas-liquid critical temperatures of several 1-alkanol and hydrocarbon mixtures are reported. The critical temperatures have also been calculated from the one-fluid model and the "hard sphere + attractive term" equation of state due to Guggenheim. The agreement is quite good for mixtures of similar-size molecules. The analysis provides values of an adjustable parameter, xi, which reflects the strength of unlike intermolecular interaction. The values of xi are discussed in terms of the influence of hydrogen bonding and dipole forces. Mixtures in which hydrogen bonding and dipole forces are important have xi-values which are less than would otherwise be expected. The deviation of the experimental critical temperatures from linearity between the critical temperatures of the two pure components is discussed qualitatively. The observed deviations are consistent with expected effects of the dipolar interactions and the difference in critical temperature of the pure components.