Water Spray in Atmospheric Pressure Electrical Discharge Plasma

0932481洛克该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。液体的相互作用（例如，水）与等离子体（通常是离子化气体）的反应发生在广泛的技术应用和自然现象中，包括用于关节镜手术的液相放电、用于肾结石治疗的碎石术、伤口愈合和消毒、纳米颗粒的合成、等离子体辅助燃烧、用于化学分析的微传感器、闪电放电、高压电传输中的腐蚀和使用等离子体致动器的气流控制。 气-液等离子体中的等离子体化学反应的相对未开发的领域也可以在气-液化学反应重要的工业重要应用中具有广泛的影响（例如，空气污染研究和控制以及有用化学品的生产，如甲醇或氢气和其他燃料）。 这项工作将重点研究气相放电与喷雾的小微米大小的水滴到等离子体，因为这种方法已被证明是潜在的非常节能的启动各种化学反应，包括过氧化氢的形成。 等离子体相互作用的分析，特别是在这样的系统与小水滴的化学反应，是至关重要的发展我们的理解等离子体与冷凝液体一般。 这项工作将集中在两个一般情况下1）反应产物，包括过氧化氢，氧气和氢气，从纯水与Ar和O2载气和2）形成甲醇从甲烷和水滴与Ar载体。 第一种情况对于在等离子体中引发的所有羟基自由基反应具有根本重要性，而第二种情况虽然在用于生产液体燃料的能量领域中具有显著重要性，但提供了具有合理良好表征的反应途径和机制的气-液反应的示例。拟议的工作将使用一系列实验技术，包括气溶胶颗粒尺寸测量，流动可视化，排放光谱和化学分析，以发展我们对水滴流入等离子体反应器如何形成羟基自由基等反应性化学物质的理解。 将进行耦合到等离子体化学反应的传输的数学建模。 使用分子动力学的基本分析也将进行研究与凝聚水表面的电子的基本相互作用，并协助解释实验研究。 该项目预计将导致发展有关气液环境中的等离子体如何导致活性物质的形成以及它如何影响上述一些应用的基础知识。 将在跨学科和国际环境中进行化学，机械和电气工程的本科生，博士生和博士后研究员的高级教育和培训，并将完成化学工程年轻教师的指导。

0932481LockeThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The interaction of liquid (e.g., water) with plasma (typically an ionized gas) occurs in a wide range of technological applications and natural phenomena including liquid-phase electrical discharge for arthroscopic surgery, lithotripsy for kidney stone treatment, wound healing and disinfection, synthesis of nanoparticles, plasma-assisted combustion, microsensors for chemical analysis, lightning discharges, corrosion in high-voltage electrical transmission and air flow control using plasma actuators. The relatively unexplored field of plasma-chemical reactions in gas-liquid plasma may also have a broad impact in industrially important applications where gas-liquid chemical reactions are important (e.g., air pollution study and control and the production of useful chemicals such as methanol or hydrogen and other fuels). This work will focus on studying a gas-phase electrical discharge with a spray of small micron-size water droplets into the plasma because this approach has been shown to be potentially very energy efficient for initiating a variety of chemical reactions, including the formation of hydrogen peroxide. Analysis of plasma interactions, particularly the chemical reactions initiated in such systems with small droplets of water, is vital to developing our understanding of plasma with condensed liquids in general. This work will focus on two general cases of 1) reaction products, including hydrogen peroxide, oxygen, and hydrogen, from pure water with Ar and O2 carrier gases and 2) formation of methanol from methane and water droplets with Ar carrier. The first case is of fundamental importance for all hydroxyl radical reactions initiated in the plasma and the second, while of significant importance in the energy field for production of liquid fuels, provides an example of gas-liquid reactions with reasonably well characterized reaction pathways and mechanisms. The proposed work will use a range of experimental techniques including aerosol particle size measurements, flow visualization, emissions spectroscopy, and chemical analysis to develop our understanding of how reactive chemical species like hydroxyl radicals are formed by water droplets flowing into a plasma reactor. Mathematical modeling of the transport coupled to the plasma chemical reactions will be conducted. Fundamental analysis using molecular dynamics will also be conducted to study the basic interactions of electrons with condensed water surfaces and to assist in interpretation of the experimental studies. This project is expected to lead to the development of fundamental knowledge on how plasma in gas-liquid environments leads to the formation of reactive species and how it affects some of the applications mentioned above. Advanced education and training of undergraduate students, PhD students, and a postdoctoral researcher in chemical, mechanical, and electrical engineering in an interdisciplinary and international environment will be conducted, and the mentoring of a young faculty member in chemical engineering will be accomplished.