THE CRITICAL PROPERTIES OF DILUTE N-ALKANE MIXTURES

The critical properties of several dilute mixtures of n-hexane (solven t) with n-decane, n-tetradecane, n-octadecane, and n-docosane were mea sured using two experimental methods developed in our laboratory. The two methods are a sealed ampoule method for the measurement of the cri tical temperature and the critical density; and a flow method, which i s used for the measurement of the critical temperature and pressure. B oth methods have been used successfully by us to measure the critical properties of many thermally stable and unstable fluids and fluid mixt ures. In the present work, the limiting slopes of the critical lines a t infinite dilution were determined and compared with predictions from an equation of state. The application of these slopes for the predict ion of phase equilibria in the dilute critical region was also explore d, making use of recent theoretical developments in this field.