功能化离子液体作为一种新兴的绿色材料,具有广泛的应用前景.采用高精度红外热成像系统,研究了高浓度四甲基铵甘氨酸离子液体和甘氨酸钠水溶液在均匀加热的竖直平板上的降膜过程.实验结果表明:Marangoni效应普遍存在于流体降膜过程中,且主要受到加热温差以及体系粘度的影响.实验还首次观测到高浓度二元离子液体体系降膜过程中的分叉流型,通过分析比较了此分叉流型的发生条件,为进一步的工业应用提供了依据.
The task specific ionic liquids have been a very hot issue in these years due to their excellent physical and chemical properties.Among these,the amino acid ionic liquids are expected to replace the organic amines in the process of sour gases(CO2,SO2,et al.) absorption and separation.First,the fluidity and the heat-/mass-transfer properties should be studied.The falling film characteristics of tetramethyl-ammonium glycine ionic liquid and sodium glycinate aqueous solutions of high concentrations on a uniformly-heated vertical plate were experimentally investigated with a highly sensitive infrared camera system.The results showed that the Marangoni effect commonly existed in the process and it was affected mainly by the heated temperature difference and the viscosity.The effect of the solute becomes distinct with the increasing of its concentration.A bifurcate flow pattern was observed for the first time in the falling film of binary system of high concentrations.The generating conditions of such brifurcate flow pattern were analyzed and provided evidences for the further industrial application.