Characterization of the Ability of CO2 to Act as an Antisolvent for Ionic liquid/organic Mixtures

Berlyn R Mellein, Joan F Brennecke

J Phys Chem B. 2007 May 10;111(18):4837-43.

PMID: 17311451

Abstract:

This paper discusses the ability of CO2 to induce liquid/liquid-phase separation in mixtures of ionic liquids and organics. New data for the solubility of CO2 in the ionic liquid/organic mixtures and the volume expansion of the mixtures with added CO2 are used to analyze the results. Acetonitrile, 2-butanone, and 2,2,2-trifluoroethanol are chosen to distinguish dipolar and hydrogen-bonding interactions. Likewise, 1-n-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, 1-n-hexyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide, 1-n-hexyl-3-methylimidazolium triflate, and ethyl-dimethyl-propylammonium bis (trifluoromethylsulfonyl)imide were studied to vary hydrogen-bond-donating and -accepting abilities of the ionic liquids. Primarily, the ability of CO2 to act as an antisolvent depends on the solubility of the CO2 in the ionic liquid/organic mixture. Strong hydrogen bonding between the ionic liquid and the organic makes it more difficult for CO2 to induce a liquid/liquid-phase separation.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP258273777	Ethyldimethylpropylammonium bis(trifluoromethylsulfonyl)imide		258273-77-7	Price