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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 3: Ionic Liquids
CPP 3.4: Talk
Monday, March 31, 2014, 10:15–10:30, ZEU 260
Volatility of ionic liquids at the nanoscale by means of ultra-fast scanning calorimetry — •Mathias Ahrenberg1, Marcel Brinckmann1, Jürn W.P. Schmelzer1, Martin Beck2, Christin Schmidt3, Olaf Keßler2, Udo Kragl3, Sergey P. Verevkin3, and Christoph Schick1 — 1Institute of Physics, University of Rostock, Wismarsche Str. 43-45, 18051 Rostock, Germany — 2Faculty of Mechanical Engineering and Marine Technology, University of Rostock, Albert-Einstein-Str. 2, 18059 Rostock, Germany — 3Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 3a, 18059 Rostock, Germany
The determination of vaporization enthalpies of extremely low volatile ionic liquids is challenging and time consuming due to the low values of vapor pressure. In addition, these liquids tend to decompose already at temperatures where the vapor pressure is still low. Conventional methods for determination of vaporization enthalpies are thus limited to temperatures below the decomposition temperature. Here we present a new method for the determination of vaporization enthalpies of such liquids using differential fast scanning calorimetry. We have developed and proven this method using [EMIm][NTf2] at temperatures up to 750 K and in different atmospheres. It was demonstrated that evaporation is still the dominating process of mass loss even at such highly elevated temperatures. Since the method allows very high heating rates (up to 100000 K/s), much higher temperatures can be reached in the measurement of the mass loss rate as compared to common devices without significant decomposition of the ionic liquid.