EAGER: Viologen-catalyzed Electrochemical Conversion of Biomass for Sustainable Energy and Products

来自生物质的碳水化合物具有为电动汽车和其他电力消耗需求产生可再生能源的潜力。目前阻碍这项技术的挑战包括生物燃料电池的低功率输出和催化剂耐久性不足，以及非生物燃料电池的低碳水化合物转化率。一项变革性的突破是发现了一种均匀的非生物催化剂，可以实现几乎完全的碳水化合物转化。该项目的总体目标是探索利用这一突破在电化学反应器中通过生物质转化生产可持续能源的可行性。这项初步可行性研究将确定关键的基本过程和制约因素，这些过程和制约因素将决定反应堆系统的设计和运行，以生产可持续能源、燃料或生化产品。为实现这一目标，确定了四项任务。任务1将确定是否可以有效地平衡均相和非均相反应速率，以获得可持续的、经济上可行的工艺所需的电流密度。在受控流动条件下的实验将受到pH、反应物浓度、温度和电位的影响。任务2将根据任务1中确定的条件，探索在实际反应器系统中促进近乎完全的碳水化合物转化的策略。任务3将评估氢气生产作为电力生产替代方案的可行性。具有更多负氧化还原电位的紫罗兰将被评价为可能的催化剂。最后，任务4将根据前面任务的结果确定和量化拟议的电力或氢气发电系统的基本特性和局限性。作为这项任务的一部分，还将探索在均相和非均相反应中使用单独反应器的可能性，以潜在地实现更高的效率和额外的转化产品。这项初步研究的完成将1)确定新发现的viologen催化剂是否可以用于高速率（电流密度）的碳水化合物转化，以证明进一步考虑将该系统作为完整提案的一部分，2)确定一种反应器策略，通过该策略可以从碳水化合物的近乎完全转化中产生电力，3)探索使用碳水化合物产生氢气的可行性。从根本上说，本研究将研究均相生物质反应，非均相电化学反应以及反应条件的相互作用，以实现碳水化合物转化为可持续能源的潜在转化。与碳酸盐形式的碳去除有关的基本问题也将在潜在反应器策略的背景下进行探讨。预计这项研究的结果可能对发展可行和可持续的生物质转化战略产生深远的影响，重点是能源和运输燃料。固有的是利用碳水化合物近乎完全转化的多种平台（电、氢和生物活性物种）的潜在好处，以增加对生物质经济发展的吸引力。增加采用和持续使用专用能源作物的生物质工艺可以(i)减少对石油等其他能源的依赖，（ii）减少化石燃料对全球气候变化的影响，（iii）减少目前专用于生物燃料生产的粮食作物的使用。研究生和本科生，包括那些来自代表性不足群体的学生，将(i)获得可再生资源使用的设计和实施过程的经验；（ii）展示在工程限制下开发可持续过程的赞赏；（iii）在团队合作时展示有效的团队合作和领导技能；（iv）认识到可再生资源可以应用于多个过程平台的程度。

Harb, 1540537Carbohydrates from biomass have the potential to generate renewable energy for electric automobiles and other power-consuming needs. Current challenges inhibiting this technology include the low power output and insufficient catalyst durability of biofuel cells, and low carbohydrate conversion in non-biological fuel cells. A transformative breakthrough has come with the discovery of a homogeneous non-biological viologen catalyst that enables almost complete carbohydrate conversion. The overall objective of this project is to explore the feasibility of using this breakthrough to produce sustainable energy through biomass conversion in an electrochemical reactor. This preliminary feasibility study will identify the key fundamental processes and constraints that will determine the design and operation of a reactor system to produce sustainable energy, fuel or biochemical products.Four tasks have been defined to accomplish this objective. Task 1 will determine whether the homogenous and heterogeneous reaction rates can be effectively balanced to obtain the current density needed for a sustainable, economically viable process. Experiments under controlled flow conditions will the influence of pH, reactant concentrations, temperature, and potential. Task 2 will explore strategies, informed by the conditions identified in Task 1, for promoting near-complete carbohydrate conversion in a practical reactor system. Task 3 will assess the feasibility of hydrogen production as an alternative to electricity production. Viologens with more negative redox potentials will be evaluated as possible catalysts. Finally, Task 4 will identify and quantify fundamental properties and limitations of the proposed electricity or hydrogen generating system based on results from the previous tasks. The possibility of using separate reactors for the homogeneous and heterogeneous reactions will also be explored as part of this task to potentially enable greater efficiency and additional, transformative products. Completion of this preliminary study will 1) determine if the newly discovered viologen catalyst can be used for carbohydrate conversion at high rates (current density) in order to justify further consideration of this system as part of a full proposal, 2) identify a reactor strategy by which it may be possible to produce electricity from near-complete conversion of a carbohydrate, and 3) explore the feasibility of using carbohydrates to generate hydrogen. Fundamentally, this research will examine the interaction of homogeneous biomass reactions, a heterogeneous electrochemical reaction, and the reaction conditions in order to achieve potentially conversion of carbohydrates to produce sustainable energy. Fundamental issues related to carbon removal in the form of carbonate will also be explored in the contextof potential reactor strategies. It is expected that the results of this study could have a far-reaching impact on the development of viable and sustainable biomass conversion strategies, with emphasis on energy and transportation fuels. Inherent is the potential benefit of multiple platforms (electricity, hydrogen, and biologically reactive species) utilizing near-complete conversion of carbohydrates to increase the appeal for development of biomass-based economies. Increased adoption and sustained use of biomass-based processes from dedicated energy crops could (i) reduce dependence on other energy resources such as petroleum, (ii) reduce the impact of fossil fuels on global climate change, and (iii) reduce the use of food crops currently dedicated for biofuel production. Both graduate and undergraduate students, including those from underrepresented groups, will (i) gain experience in the design and implementation process for use of renewable resources (ii) demonstrate an appreciation for working within engineering constraints to develop a sustainable process, (iii) demonstrate effective teamwork and leadership skills as they work together as a team, and (iv) recognize the extent to which renewable resources can be applied to multiple process platforms.