Homogeneous nucleation of binary vapors partially miscible in liquid state

A general analysis of nucleation in a vapor phase containing two components that are partially miscible in the liquid state is presented. The analysis has been applied to three systems: diethylene glycol+n-heptane, methanol+cyclohexane and diethylene glycol+benzene. On the basis of the classical nucleation theory, the results indicate that a range of saturation ratios, depending on the degree of miscibility, leads to the formation of two types of critical nuclei differing in size and composition. The likelihood of formation of two types of critical nuclei increases as the miscibility gap of the system increases. In some situations, both kinds of nuclei can have the same free energy of formation, and can nucleate at the same rate.