Experimental measurements of Vaughan and Collins [Ind. Eng. Chem., 34,885 (1942)] for the propane-isopentane system at 167°F and 147 psia show for propane a liquid-phase mole fraction of 0.2900 in equilibrium with a vapor-phase mole fraction of 0.6650. Calculate:
(a) The K-values for C3 and iC5 from the experimental data.
(b) Estimates of the K-values of C3 and iC5 from Raoult's law assuming vapor pressures at 167oF of 409.6 and 58.6 psia, respectively. Compare the results of
(a) and (b).
Assuming the experimental values are correct, how could better estimates of the K-values be achieved? To respond to this question, compare the rigorous expression Ki = γiLФiL/ФiV to the Raoult's law expression Ki = Psi/ P.