Mass transfer and dispersion enhancement using oscillatory motion and nanofluids

过程的强化和绿色技术的实施，如膜分离技术，为应对消费者需求的快速发展和公众对环境和安全的担忧而产生的挑战提供了非常有希望的方法。遗憾的是，这些技术大多受到浓差极化、表面污垢和低分子扩散导致的低传输率的限制。在许多应用中，如气-液、液-液和固-液系统中，使用振荡运动已被证明在提高传输率方面是有效的。它还可用于提高受分子扩散限制的应用的性能，如支撑液膜，它们正在成为传统液体萃取的有希望的替代方案。然而，这仍然需要更多的研究来确定振荡对涉及的流动模式和传递机制的影响及其对整体增强的贡献。另一种可能应用于提高传输率的技术是使用纳米流体。事实证明，这种方法在改善导热系数方面是有效的，因此可能会以类似的方式影响质量传输。将其与振荡运动相结合，可以为提高受分子扩散和/或低界面传输率限制的应用的性能提供一个有吸引力的选择。遗憾的是，目前还没有关于纳米流体用于传质或增强分散的信息。该研究计划的主要目标是解决上述问题，并获得所需的知识，以便能够有效地利用振荡运动和纳米流体进行传质和分散增强。这项研究计划的第二个目标是研究使用被动手段(如自我维持振荡)作为强迫振荡的替代方案来实现最佳振荡条件的可能性，因为强迫振荡增加了过程的复杂性和能量消耗。

Process intensification and implementation of green technologies such as membrane separation techniques offer very promising approach to meet the challenges stemming from rapid development in consumer demand and constraints from public concern over environment and safety. Unfortunately most of these technologies are limited by low transfer rates caused by concentration polarization, surface fouling and low molecular diffusion. Use of oscillatory motion has proven effective in increasing transfer rates in many applications such as gas-liquid, liquid-liquid, and solid-liquid systems. It can also be used for enhancing performance of applications limited by molecular diffusion such as supported liquid membranes which are emerging as promising alternative to conventional liquid extraction. This however still requires more investigation to determine the effect of oscillation on flow patterns and transfer mechanisms involved and its contribution to the overall enhancement. Another technique that can potentially be applied for augmenting transfer rates is the use of nanofluids. The approach has proven effective in improving thermal conductivities and could therefore affect mass transport in a similar way. Combining this with oscillatory motion could offer an attractive option for enhancing the performance of applications limited by molecular diffusion and/or low interfacial transfer rate. Unfortunately, no information is available on the use of nanofluids for mass transfer or dispersion enhancement. The main objective of this research program is address the above issues, and to gain the required knowledge to enable the effective use of oscillatory motion and nanofluids for mass transfer and dispersion enhancement. A second objective of this research program is to investigate the potential of achieving optimum oscillatory conditions using passive means such as self-sustained oscillation as an alternative to forced oscillation which adds to the complexity and energy consumption of the process.