THERMODYNAMICS OF BRANCHED ALCOHOLS .1. EXTENSION OF DISQUAC TO TERT-ALCOHOLS-N-ALKANES OR TERT-ALCOHOLS-CYCLOHEXANE MIXTURES

DISQUAC interchange coefficients for the contacts tertiary OH-aliphati c and tertiary OH-cyclohexane are reported. The quasichemical paramete rs are independent of the alkane; the first and third quasichemical pa rameters are common for the alkanols investigated, whereas the second depends on the position of the OH group. Therefore, two ensembles of a lcohols are distinguished: 2-methyl-2-alkanols and 3-methyl-3-alkanols . Tert-butanol behaves differently owing to its high melting point. Di spersive parameters change with the alcohol. This behaviour is compare d with that observed for other contacts. Vapor-liquid equilibria and e xcess functions, even the excess heat capacity, are well represented b y the model. In contrast, partial molar excess quantities at infinite dilution are poorly described.