TEMPERATURE DEPENDENCIES OF SPREADING COEFFICIENTS OF HYDROCARBONS ONWATER

This paper describes experimental work on the equilibrium spreading co efficient of one liquid on another, S, at elevated temperatures and pr essures, and also an attempt to provide a universal correlation for S as a function of temperature T. The new data together with those obtai ned in the preceding work (Takii and Mori, J. Colloid Interface Sci. 1 61, 31 (1993)) cover n-octane/water at 0-150 degrees C and n-heptane/w ater at 0-70 degrees C. It is demonstrated that these data are correla ted, with reasonable accuracy, by a single formula having the form S(T )/S-i = f[(T - T-i)I(T-c - T-i)], where T-i and T-c denote the ice poi nt of water and the critical-point temperature of each hydrocarbon, re spectively, and S-i denotes S at the ice point. (C) 1995 Academic Pres s, Inc.