Enhancement of Gas-liquid Mass Transfer using Magnetite Nanoparticles

CBET-0827894 Mathews化学和生物分离计划的NSF奖项支持堪萨斯州立大学的亚历山大P.马修斯教授的工作，以研究使用纳米颗粒和纳米壳作为穿梭器来增强气液传质和反应速率的方法和机制。纳米颗粒和介孔纳米壳层具有独特的性质，如高表面积和流动性，这些可以用来改变气液传质中的气泡性质。纳米颗粒尺寸在流体动力学边界层的范围内，并且可以用于跨边界层输送质量。此外，吸附剂纳米颗粒可以从液相中吸附溶质并将溶质快速穿梭到气相。由于（1）除了液-气传质之外的平行液-固-气传质机制，（2）增加的气泡停留时间，和（3）空化气泡和在超声场下，预期该方法提供传质速率的数倍增加。本研究将探讨的机制，惰性和吸附剂纳米粒子将影响传质速率的溶解有机污染物从水转移到空气中的存在和不存在的超声波场。气液传质过程在自然和工程系统中是重要的。从这项工作中获得的知识的应用将提供更有效的手段进行质量转移操作在饮用水净化，多相反应的过程中的工业，并在去除挥发性有机化合物从污染的地下水和废水。

CBET-0827894MathewsThis NSF award by the Chemical and Biological Separations Program supports work by Professor Alexander P. Mathews of Kansas State University to investigate methods and mechanisms to enhance gas-liquid mass transfer and reaction rates using nanoparticles and nanoshells as shuttles. Nanoparticles and mesoporous nanoshells possess unique properties such as high surface area and mobility, and these can be used to advantage in changing bubble properties in gas-liquid mass transfer. Nanoparticle sizes are in the range of hydrodynamic boundary layers, and can be used to transport mass across the boundary layer. Moreover, adsorbent nanoparticles can sorb solutes from the liquid phase and rapidly shuttle the solutes to the gas phase. This process is expected to provide several fold increase in mass transfer rates due to (1) a parallel liquid-solid-gas transfer mechanism in addition to liquid-gas mass transfer, (2) increased bubble residence time, and (3) cavitating bubbles and under ultrasonic fields. This research will examine the mechanisms by which inert and adsorbent nanoparticles will affect mass transfer rates in the transfer of dissolved organic contaminants from water to the air phase in the presence and absence of ultrasonic fields. Gas-liquid mass transfer processes are important in natural and engineered systems. The application of knowledge gained from this work will provide more efficient means of conducting mass transfer operations in drinking water purification, multiphase reactions in the process industries, and in the removal of volatile organic compounds from contaminated groundwaters and wastewaters.