Vapor Phase Homogeneous Nucleation of Higher Alkanes: Dodecane, Hexadecane, and Octadecane. 2. Corresponding States and Scaling Law Analysis

Abstract

The results from corresponding states and scaled nucleation models indicate that the nucleation behavior of the normal alkanes follows a predictable trend. Systematic deviations from ideal fluid behavior can be correlated to physical properties, such as the increase in the entropy of vaporization and the increase in the excess surface entropy of the nucleating clusters. Hale's scaled nucleation model allows for the accurate prediction of nucleation threshold behavior for the alkanes. Experimental agreement with the model is maintained throughout the temperature range studied. The scaled model for the nucleation rate provides a better description of the experimental rates than the classical nucleation theory. The addition of extra terms to the classical expression of the free energy of cluster formation and the inclusion of the Fisher's droplet model term significantly compensate for the strong temperature dependence present in the flux prefactor of the classical rate equation. For accurate predictions of ...