Diffusion and solubility measurements in room temperature ionic liquids

Abstract

This paper focuses on a new method for measuring the diffusion coefficients of gases in room-temperature ionic liquids (RTILs) using a semi-infinite volume approach. Henry's constants were also measured under the same conditions as the diffusion coefficients. The relationship of the Henry's constants and diffusion coefficients with temperature is discussed along with the relationship of the diffusion coefficients with molecular size and viscosity. The RTIL used was ethylmethylimidazolium bis(trifluoromethanesulfonyl)amide ([emim])-([Tf 2N]), and the gases used were ethane, ethene, propane, propene, and carbon dioxide. © 2006 American Chemical Society.