Excess molar enthalpies for ( n-hexane + n-hexadecane) and for three- and four-component alkane mixtures simulating this binary mixture

Abstract

Excess molar enthalpies H m E are reported at 0.1 MPa for { xC 6H 14 + (1− x)C 16H 34} at 298.15 and 303.15 K and for three- and four-component mixtures of n-alkanes, simulating the binary mixture, at 303.15 K. Isothermal dilution calorimetry was employed, using initial liquids which were either pure or binary mixtures with average carbon numbers of 6 and 16. The results for the multicomponent mixtures are compared with those for the binary mixtures via the principle of congruence which is found to be capable of correlating the results for all mixtures within 4 per cent of H m E(max.). Values of H m E(max.) for the multicomponent systems are slightly less than for the binary mixture and appear to decrease as the number of components increases.