I&EC 9 |
| Ionic liquids exhibit unique properties: they are liquid over a wide temperature range, non-volatile, non-flammable, and possess exceptional thermal, chemical and electrochemical stability. But, they are much more viscous then conventional organic solvents. Recently, we developed a model which helps to understand the influence of coordination ability of the anions on the viscosity of ionic liquids. If the counter-anions are sufficiently nucleophilic (for instance chloride), they can coordinate to the cations to form contact ion-pairs, ion-clusters or solid salts. In this case we should take into account a co-operative diffusion of anion and cation. If the counter-anions are weakly coordinating with distinctly delocalized negative charge and low charge density on the outer sphere, we can consider such anions as independently moving particles. In this case the radius of the sphere is much smaller and consequently the diffusion coefficient (D) and mobility of ions are much higher leading to lower viscosity. |
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Ionic Liquids: Not Just Solvents Anymore OR Ionic Liquids: Parallel Futures (Sponsored by Green Chemistry and Engineering, Separation Science and Technology and Novel Chemistry with Industrial Applications Sub-Divisions)
8:15 AM-12:25 PM, Sunday, 26 March 2006 Georgia World Congress Center -- B314, Oral
Division of Industrial and Engineering Chemistry |