Laboratory of Environmental Engineering, Department of Process Engineering, Faculty of Engineering, Badji Mokhtar - Annaba University, P.O. Box 12, 23000 Annaba, Algeria; Laboratory of Environmental Process Engineering, Department of Chemical Engineering, Faculty of Process Engineering, University of Constantine 3, 25000 Constantine, Algeria.
Laboratory of Environmental Engineering, Department of Process Engineering, Faculty of Engineering, Badji Mokhtar - Annaba University, P.O. Box 12, 23000 Annaba, Algeria.
Ultrason Sonochem. 2018 Mar;41:143-155. doi: 10.1016/j.ultsonch.2017.09.035. Epub 2017 Sep 21.
In this work, a comparison between the temperatures/pressures within acoustic cavitation bubble in an imidazolium-based room-temperature ionic liquid (RTIL), 1-butyl-3-methylimidazolium bis(triflluoromethyl-sulfonyl)imide ([BMIM][NTf]), and in water has been made for a wide range of cavitation parameters including frequency (140-1000kHz), acoustic intensity (0.5-1Wcm), liquid temperature (20-50°C) and external static pressure (0.7-1.5atm). The used cavitation model takes into account the liquid compressibility as well as the surface tension and the viscosity of the medium. It was found that the bubble temperatures and pressures were always much higher in the ionic liquid compared to those predicted in water. The valuable effect of [BMIM][NTf] on the bubble temperature was more pronounced at higher acoustic intensity and liquid temperature and lower frequency and external static pressure. However, confrontation between the predicted and the experimental estimated temperatures in ionic liquids showed an opposite trend as the temperatures measured in some pure ionic liquids are of the same order as those observed in water. The injection of liquid droplets into cavitation bubbles, the pyrolysis of ionic liquids at the bubble-solution interface as well as the lower number of collapsing bubbles in the ionic liquid may be the responsible for the lower measured bubble temperatures in ionic liquids, as compared with water.
在这项工作中，比较了咪唑基室温离子液体（RTIL）1-丁基-3-甲基咪唑双（三氟甲基磺酰基）亚胺（[BMIM][NTf]）和水中的空化泡内的温度/压力，涵盖了广泛的空化参数，包括频率（140-1000kHz）、声强（0.5-1Wcm）、液体温度（20-50°C）和外部静压（0.7-1.5atm）。所用的空化模型考虑了液体的可压缩性以及介质的表面张力和粘度。结果发现，与水中预测的温度相比，离子液体中的气泡温度和压力总是高得多。在更高的声强、液体温度和更低的频率和外部静压下，[BMIM][NTf]对气泡温度的有益影响更为明显。然而，预测和实验估计的离子液体中温度之间的对比显示出相反的趋势，因为在一些纯离子液体中测量的温度与在水中观察到的温度相同。将液滴注入空化泡中、泡-溶液界面处的离子液体热解以及离子液体中较少的气泡坍塌可能是导致离子液体中测量的气泡温度低于水的原因。
