CALORIMETRIC STUDY OF NITRILE CARBONYL GROUP-INTERACTIONS - COMPARISON WITH DISQUAC PREDICTIONS

Excess enthalpies, H(E), at 298.15 K and atmospheric pressure are repo rted for binary liquid mixtures of alkanenitriles + n-alkanones. These experimental results, along with literature data on liquid-vapor equi libria (excess Gibbs energies), G(E), excess enthalpies, H(E), and act ivity coefficients at infinite dilution, gamma(i)infinity, are interpr eted in terms of the DISQUAC group contribution model. The systems are characterized by three types of contact surfaces: nitrile (CN), carbo nyl (CO) and alkane. The interchange energies of the alkane/CN and alk ane/CO contacts were determined independently from the study of n-alka ne + nitrile and n-alkane + ketone systems. The interaction parameters of the CN/CO contacts are reported in this work. The quasi-chemical p arameters for alkanenitrile + ketone are zero except for ethanenitrile -containing mixtures. The dispersive parameters depend on the environm ent of the CN and CO groups. In general, the model provides a fairly c onsistent description of the excess functions G(E) and H(E) as functio ns of composition of the n-alkanenitrile + n-alkanone mixtures investi gated.