Deferm Clio, Van den Bossche Arne, Luyten Jan, Oosterhof Harald, Fransaer Jan, Binnemans Koen
KU Leuven, Department of Chemistry, Celestijnenlaan 200F, bus 2404, B-3001 Heverlee, Belgium.
Phys Chem Chem Phys. 2018 Jan 24;20(4):2444-2456. doi: 10.1039/c7cp08556g.
Dynamic TGA studies of phosphonium ionic liquids have reported thermal stabilities of 300 °C or higher for these compounds. This is often an overestimation of the real thermal stability. The chosen technique as well as the experimental parameters can influence the thermal stability. In this paper, the thermal stability of commercially available Cyphos IL 101 is studied. The effect of the nature of the atmosphere (air or inert gas), the purity of the sample, the heating rate and presence of a metal on the short-term and long-term stability of commercial Cyphos IL 101 is investigated. The thermal decomposition products are characterized using thermogravimetric analysis coupled to mass spectrometry (TGA-MS). Impurities present and higher heating rates lead to an under- and overestimation of the thermal stability, respectively. The presence of oxygen leads to a lower thermal stability. In contrast, adding metal chlorides to the ionic liquid causes an increase in the thermal stability. The chloride anions are coordinated to the metal ion, so that the Lewis basicity of the anions is reduced. Also this paper gives insights in the behavior of Cyphos IL 101 at high temperatures, which is of relevance for possible application of this ionic liquid in high-temperature industrial processes.
关于鏻离子液体的动态热重分析（TGA）研究报告称，这些化合物的热稳定性为300°C或更高。这往往高估了其实际热稳定性。所选用的技术以及实验参数会影响热稳定性。本文研究了市售Cyphos IL 101的热稳定性。研究了气氛性质（空气或惰性气体）、样品纯度、加热速率以及金属的存在对市售Cyphos IL 101短期和长期稳定性的影响。使用热重分析联用质谱（TGA-MS）对热分解产物进行了表征。存在杂质和较高的加热速率分别导致对热稳定性的低估和高估。氧气的存在会导致热稳定性降低。相反，向离子液体中添加金属氯化物会导致热稳定性增加。氯离子与金属离子配位，从而降低了阴离子的路易斯碱性。本文还深入探讨了Cyphos IL 101在高温下的行为，这对于该离子液体在高温工业过程中的可能应用具有重要意义。
