Collaborative Research: Self-circulating, self-regulating microreactor for on-chip gas generation from liquid reactants

项目负责人：朱利坤(1)，于慧丹(1)，门德生(2),Craig R. Friedrich(2)研究机构：(1)美国印第安纳大学，(2)美国密歇根理工大学提案号：(1)1264739和(2)1264549在许多类型的化学反应器中，包括微电源、片上细胞培养系统、气液合成、微火焰电离探测器、太阳能水分解系统和微生物电解电池（MEC），以降低寄生功耗和寄生质量产生和处理气态物质已经成为越来越大的挑战。为了解决这一挑战，提出了一种自循环、自调节的机制，根据需要从液体反应物中产生气态物质。该系统的寄生功耗很小或为零，不需要离散控制系统进行调节。本工作旨在了解具有自循环和自我调节功能的集成微流体气体发生器的过程控制和动力学。这项工作有望为高效、自主、按需燃气发生系统的许多应用奠定工程和科学基础。为了实现这一目标，研究工作将首先集中在对微流控网络中反应性多相流的基本理解上，并提出自调节、自循环机制。过氧化氢催化分解将作为一个基本模型系统进行基础研究。实验研究了气泡驱动的液体循环动力学、自调节、气液分离机理和反应物利用。综合晶格玻尔兹曼方法（LBM）模型将用于研究气体发生器的物理特性。气泡动力学是数值研究的热点。LBM模型和相关的数值模拟将为实验提供基准，并指导未来的设计。微型反应器配置将在两种应用上进行测试：用于便携式电子设备的高性能小型燃料电池和mec的能源回收/废水处理。与这两种特殊应用有关的问题将用于为今后的商业化奠定基础。微反应器中多相流的高效管理和利用具有广泛的应用前景。这项研究的成功实施可以直接促进基于燃料电池的高能量密度发电设备的发展，在燃料电池中，氢的储存和输送仍然是主要的技术挑战。所提出的方法可能有助于克服这一问题，实现自动泵送和控制按需制氢，而对系统复杂性和包装的负担很小。这项工作也将有利于一系列便携式应用，如便携式电子设备、植入式生物医学设备和具有无线通信能力的分布式微系统。此外，它还有助于开发可扩展的微生物电解电池，用于从可再生能源制氢，同时在废水排放前进行清理。它有望进一步激发类似的方法在片上细胞培养系统，微火焰电离探测器，太阳能水分解系统等。教育工作将通过当地社区少数民族学生的参与而受益。夏令营将在两个校区组织，为当地高中生提供探索微/纳米技术跨学科领域的机会。

PI: Likun Zhu(1), Huidan Yu (1), Desheng Men(2), Craig R. Friedrich(2)Institutions: (1) Indiana University, (2) Michigan Technological UniversityProposal Numbers: (1) 1264739 and (2) 1264549Title: Collaborative Research: Self-circulating, self-regulating microreactor for on-chip gas generation from liquid reactantsGeneration and handling of gaseous species with reduced parasitic power consumption and parasitic mass has been a growing challenge in many types of chemical reactors, including micro power sources, on-chip cell culturing systems, gas-liquid synthesis, micro flame ionization detectors, solar water splitting systems, and microbial electrolysis cells (MEC). To address this challenge, a self-circulating, self-regulating mechanism is proposed to generate gaseous species from liquid reactants on demand. The system involves little or zero parasitic power consumption and needs no discrete control system for regulation.Intellectual MeritThis work seeks to understand the process control and dynamics of an integrated microfluidic gas generator with self-circulation and self-regulation functionalities. This work is expected to establish the engineering and scientific foundation for highly-efficient, autonomous, on-demand gas generation systems for many applications. To achieve this objective, the research efforts will first be focused on fundamental understanding of the reactive multiphase flow in a microfluidic network with the proposed self-regulation, self-circulation mechanism. Catalytic decomposition of hydrogen peroxide will be employed as a basic model system to perform the fundamental studies. The dynamics of bubble-driven liquid circulation, self-regulation, mechanism of gas/liquid separation, and reactant utilization will be experimentally investigated. A comprehensive lattice Boltzmann method (LBM) model will be used to study the physics in the gas generator. Bubble dynamics is a focus for the numerical study. The LBM model and the related numerical simulation will be used to provide benchmarks for the experiments and to guide future designs. The micro reactor configuration will then be tested on two applications: high-performance small fuel cells for portable electronics and energy reclamation/treatment of waste water by MECs. The issues related to these two particular applications will be used to establish the foundation for future commercialization.Broader ImpactEfficient management and utilization of multiphase flow in microreactors have a broad range of applications. The successful implementation of this research could directly facilitate the development of high-energy-density power generation devices based on fuel cells, where hydrogen storage and delivery remain major technical challenges. The proposed approach may help overcome this problem by achieving autonomous pumping and control for on-demand hydrogen generation with little burden on system complexity and packaging. The work could also benefit a series of portable applications, such as portable electronics, implanted biomedical devices, and distributed microsystems with wireless communication capability. In addition, it could also benefit the development of scalable microbial electrolysis cells for hydrogen generation from renewable energy sources, while cleaning up waste water before its discharge. It is expected to further inspire similar approaches in on-chip cell culturing systems, micro flame ionization detector, solar water splitting systems, etc. Educational efforts will benefit through the involvement of minority students from the local community. Summer camps will be organized on both campuses to provide local high school students an opportunity to explore the interdisciplinary fields of micro/nanotechnology.