Viscosity and spin-lattice relaxation time of supercritical carbon dioxide-n-hexadecane mixtures, and molar density and isobaric heat capacity ratios for dense fluids

[摘要] In part one, correlations between viscosity and proton spin-lattice relaxation time are developed for CO$sb2$ - n-Hexadecane mixtures in equilibrium with their vapor-phase in the vicinity of critical points. A microscopic interpretation of relaxation phenomena is presented based on the Rate Processes Theory$sp{12}$. It is found that by comparing with n-Hexadecane relaxation times at the same thermodynamics conditions, local motions of n-Hexadecane molecules increase when CO$sb2$ molecules are added. In part two, it is shown that for two fluids with similar interaction potentials, at a given pressure and temperature, the ratio of the molar densities is equal to the inverse of the ratio of the molar isobaric heat capacities. This relation is extended to mixtures and is applied to several hydrocarbons and mixtures. Differences found between the two ratios would suggest that the two fluids do not have similar interaction potentials.

[发布机构] Rice University