Ionic Liquids as Heat Transfer Medium

T.J.S. Schubert, H. Sahin, M. Götz, K. Bär, D. Buchholz, F. Stiemke
IOLITEC Ionic Liquids Technologies Inc., US

Keywords: thermal fluid, heat transfer, ionic liquids, commercial application


Ionic liquids are defined as pure salts with melting points below 100°C. Their high heat capacity, low vapor and incombustibly make them to promising candidates as thermal fluids. A limiting factor thereby is the resistance to thermal decomposition. Many ILs are misleadingly reported in the literature to be stable to high temperatures.In case of short-term heating, there are ionic liquids which are stable up to 400°C. However, the major challenge is to create fluids with a long-term thermal stability. Based on our investigations we will report an overview about thermally stable ILs. By pre-selecting a comprehensive matrix of different anions and cations from our substance library of more than 600 compounds, using known physical and chemical data from literature and from our data pool, we identified in carefully chosen screening tests novel interesting structural motifs. The relation between structure and technical performance will be discussed, leading finally to an outlook of upcoming commercial applications.