Chemical Reaction Activation in Microreactors Through Corona Discharge

通过电晕放电激活微反应器中的化学反应

• 批准号: 1134249
• 负责人: Alexandre Yokochi
• 金额: $ 33.06万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1134249&HistoricalAwards=false
• 关键词: Chemical; Reaction; Activation; Microreactors; Through

Proposal Number: 1134249PI: Yokochi, Alexandre F. Molecules involved in chemical reactions require sufficient energy to overcome the activation energy barrier. This is true in spontaneous reactions at room temperature the fact that they are spontaneous merely means that the required energy is present in the form of ambient thermal energy. In a few cases this activation energy barrier can be lowered through the use of catalysts, and in some the energy can be supplied in alternative forms (other than sensible heat) such as sonochemical, photochemical, and electrical discharge. The primary objective of this work is to examine how non-thermal plasmas generated by electrical discharge through fluids may be used to drive chemical reactions in microchannel reactors. The model reactions chosen are the oxidation of organic molecules dissolved in aqueous media by dissolved atmospheric oxygen and the partial oxidation of methane to methanol. Preliminary work has demonstrated that the corona discharge activated oxidation takes place, and the technical literature suggests that electrical discharge activation of the partial oxidation of methane also occurs. The development of an efficient corona discharge activated microchannel reactor could lead to both an efficient approach to tertiary treatment of potable water by advanced oxidation and a method to constructively use stranded methane that is currently too expensive to recover, and also develop an entirely novel approach to the general activation of chemical reactions that will open new process reaction options for various applications. An important barrier to the implementation of electro-discharge processes in microreactors is the high voltage required to achieve spark or dielectric barrier discharge. The required voltages can be greatly diminished by enhancing the emitter electrode with carbon nanotubes.Intellectual Merit: This project will systematically explore the development and implementation of corona discharge activated chemical reactions in microchannel reactors through the construction and experimental evaluation of the performance of an experimental device and the crafting of a careful model of the reactor operation. The project will be approached in the following manner:1. Exploratory implementation of corona discharge activated reactive systems in microreactors: This will explore the manner in which a microchannel reactor within which a chemical reaction can be activated by corona discharge can best be built. In particular, the best methodology for the enhancement of the emitter electrodes with carbon nanotubes will be evaluated.2. Experimental evaluation of the corona discharge driven oxidation in aqueous media: Using the CNT enabled corona discharge activated microreactor developed in task 1, the effect of varying reaction conditions will be evaluated. Factors to evaluate include applied potential, total power, thickness of the reactor channel, fluid flow rate (i.e., residence time) and dissolved oxygen concentration.3. Partial oxidation of methane to methanol: Using the CNT enabled corona discharge microreactor, proof of concept followed by full exploration of process parameters will take place. Similar factors as described in 2 will be evaluated with the addition of methane/H2O/O2 ratios in the reactor performance.4. Development of an explanatory/predictive model for the corona activated microreactor: Using the data collected in Tasks 2 and 3, a model of the reactor will be developed using COMSOL in which the effects of the factors described above will be evaluated. The particular information to be extracted from the model includes reaction rates and the thickness of the reacting volume in the system.Educational Integration: The reactor system described will be used as a basis for formal education by developing 1) an experimental module where early program undergraduates inChemical/Environmental Engineering can actually work with an advanced chemical process including the ability of tweaking a few parameters, 2) offering advanced students in the senior capstone experience sequence the opportunity to implement chemical processes using the developed platforms and 3) continuing to mentor undergraduate researchers through hosting Johnson scholars (first year college) and SESEY (high school) students in the laboratory to work on issues based on process implementation in microreactors. These students become an integral part of the research team.Broader Impact: This research will result in the development of a novel method for chemical reaction activation within microchannel reactors, opening a new area of research for researchers developing reactive processes in microchannel reactors, hopefully enabling various future advances leading to the practical implementation of microreactor based processes. Simultaneously, the work will be used as a platform for informal (general public) and formal education for pre-college, undergraduate and graduate students (and fellow faculty!) on the issues surrounding the elimination of trace organic contaminants in potable water, and the implementation of processes in microstructured reactors in general.

提案编号：1134249 PI：Yokochi，Alexandre F.参与化学反应的分子需要足够的能量来克服活化能势垒。这在室温下的自发反应中是真实的，它们是自发的这一事实仅仅意味着所需的能量以环境热能的形式存在。在少数情况下，这种活化能势垒可以通过使用催化剂来降低，并且在一些情况下，能量可以以替代形式（除了显热）提供，例如声化学、光化学和放电。这项工作的主要目的是研究如何通过流体放电产生的非热等离子体可以用来驱动微通道反应器中的化学反应。所选择的模型反应是溶解在水介质中的有机分子被溶解的大气氧氧化和甲烷部分氧化成甲醇。初步工作已经证明发生电晕放电活化氧化，并且技术文献表明也发生甲烷的部分氧化的放电活化。有效的电晕放电激活的微通道反应器的开发可以导致通过高级氧化对饮用水进行三级处理的有效方法和建设性地使用目前太昂贵而不能回收的滞留甲烷的方法，并且还开发了化学反应的一般激活的全新方法，这将为各种应用开辟新的工艺反应选择。在微反应器中实施放电过程的一个重要障碍是实现火花或电介质阻挡放电所需的高电压。所需的电压可以大大降低通过提高发射极与碳nanotubes.Intellectual优点：本项目将系统地探讨电晕放电激活的化学反应的微通道反应器的性能的建设和实验评估的实验装置和精心制作的反应器操作模型的开发和实施。该项目将以下列方式进行：1。在微反应器中探索性地实施电晕放电激活的反应系统：这将探索微通道反应器的方式，在该微通道反应器中，可以通过电晕放电激活化学反应。特别是，最好的方法，用于增强发射极与碳纳米管将被评估。电晕放电驱动的氧化在水介质中的实验评价：使用CNT启用电晕放电激活的微反应器中开发的任务1，不同的反应条件的影响将进行评估。评估的因素包括施加的电势、总功率、反应器通道的厚度、流体流速（即，停留时间）和溶解氧浓度。甲烷部分氧化为甲醇：使用CNT使能电晕放电微反应器，将进行概念验证，然后进行工艺参数的全面探索。将在反应器性能中添加甲烷/H2O/O2比率来评估2中所述的类似因素。电晕活化微反应器的解释性/预测性模型的开发：使用任务2和任务3中收集的数据，将使用COMSOL开发反应器模型，其中将评估上述因素的影响。从模型中提取的特定信息包括反应速率和系统中反应体积的厚度。教育一体化：所描述的反应器系统将被用作正规教育的基础，方法是开发1）一个实验模块，在该模块中，化学/环境工程专业的早期课程本科生可以实际使用先进的化学过程，包括调整一些参数的能力，2）为高级顶点经验序列中的高级学生提供使用开发的平台实施化学过程的机会，3）通过在实验室中接待约翰逊学者（大学一年级）和SESEY（高中）学生，继续指导本科研究人员研究基于微反应器中过程实施的问题。更广泛的影响：这项研究将导致开发一种新的方法，用于微通道反应器内的化学反应活化，为研究人员开发微通道反应器中的反应过程开辟了一个新的研究领域，希望能够实现各种未来的进展，导致基于微反应器的过程的实际实施。同时，这项工作将作为一个平台，为大学预科，本科和研究生（和同事！）关于消除饮用水中痕量有机污染物的问题，以及一般微结构反应器中工艺的实施。