Berlin 2015 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 51: P16: New Instruments and Methods
CPP 51.5: Poster
Mittwoch, 18. März 2015, 10:00–13:00, Poster A
Determination of Volatility of Ionic Liquids at the Nanoscale by means of Ultra-Fast Scanning Calorimetry — •Mathias Ahrenberg1, Martin Beck2, Christin Schmidt3, Sergey P. Verevkin3, Olaf Kessler2, Udo Kragl3, and Christoph Schick1 — 1Institut für Physik, Universität Rostock — 2Maschinenbaufakultät, Universität Rostock — 3Institut für Chemie, Universität Rostock
Ionic Liquids (ILs) are intend to be used as quenching media in the heat treatment of metallic materials, e.g. aluminum alloys, even the solution annealing temperature of such alloys is 800 K. The most thermally stable ILs exhibit an onset temperature of decomposition at about 620 K as measured with slow scanning methods, e.g. TGA. Since in a real quenching process the IL is exposed to high temperature only shortly and in a thin layer surrounding the alloy gives reason to investigate the IL at such small scales in time and space. Here we present a new method for the determination of the mass loss rate of such liquids using differential fast scanning calorimetry. We have developed and proven this method using [EMIm][NTf2] and [BMIm][NO3] at temperatures of up to 750 K and in different atmospheres to distinguish between decomposition and evaporation. It was demonstrated that evaporation is still the dominating process of mass loss even at such highly elevated temperatures. In addition, since the method allows very high heating rates (up to 10,000,000 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.