EAGER: Catalytic Reaction Coupling of Bio-oil Hydrodeoxygenation and Alkane Dehydrogenation

开发用于从通过热解木质纤维素生物质产生的生物油制造液体运输燃料的经济上可行的技术是具有重要的社会和环境可持续性影响的巨大挑战。其中一个障碍是通过称为催化加氢脱氧（HDO）的化学反应从生物油中去除不需要的氧的高氢气需求。另一方面，页岩气技术的最新发展已经导致产生大量未充分利用的轻质烷烃，其可以用作生物油HDO的氢源。该EAGER项目的主要目标是探索使用新的双功能催化剂家族的生物油HDO和轻质（C2-C4）烷烃脱氢（DH）的直接偶联反应。所提出的探索性研究的中心假设是，由贵金属（例如，Pt）和亲氧金属（例如，Mo）在低酸性和弱电负性金属氧化物载体（例如，TiO 2）将使所提出的反应耦合方案成为可能。基于热力学分析，这种催化剂概念在理论上是可能的，但尚未得到实验证明，并且仍然未经测试。如果成功，这种催化剂将从根本上改变现有的生物油升级和烯烃生产方法。将追求三个具体的研究目标来探索这一概念的可行性：（1）将确定金属位点大小和金属-金属位点距离的影响;（2）将揭示生物油HDO位点的亲氧性的影响;（3）将表征载体组成的影响。为了获得分子水平上的理解的表面反应途径，双功能催化剂将合成与其结构控制在纳米级。催化剂活性将基于来自流动反应器实验的期望和不期望产物的产率来测量。将确定产物分布对（1）贵金属位点的尺寸、（2）DH和HDO位点之间的距离、（3）亲氧金属位点的金属-氧键强度和（4）金属氧化物载体的组成的依赖性。建议的探索性研究可能会导致催化的几何和电子效应的表面反应的化学动力学的基本理解。除了培养两名研究生外，主要研究人员还计划将研究成果纳入本科生和研究生课程。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

The development of economically viable techniques for manufacturing liquid transportation fuels from bio-oils produced by pyrolysis of lignocellulosic biomass is a grand challenge with important societal and environmental sustainability implications. One of the obstacles is the high hydrogen requirement for removing the undesired oxygen from the bio-oil via a chemical reaction called catalytic hydrodeoxygenation (HDO). On the other hand, recent developments in shale gas technologies have led to the production of vast amounts of under-utilized light alkanes, which could serve as a source hydrogen for bio-oil HDO. The main objective of this EAGER project is to explore the direct coupling reaction of bio-oil HDO and light (C2-C4) alkane dehydrogenation (DH) using a new family of bifunctional catalysts.The central hypothesis of the proposed exploratory research is that an integrated catalyst design, consisting of a precious metal (e.g., Pt) and an oxophilic metal (e.g., Mo) on a low acidic and weak electronegative metal oxide support (e.g., TiO2), will enable the proposed reaction coupling scheme. Such a catalyst concept is theoretically possible, based on thermodynamic analysis, but has not been experimentally proven and remains untested. If successful, such a catalyst will radically transform the existing bio-oil upgrading and olefin production methods. Three specific research aims will be pursued to explore the feasibility of this concept: (1) the effect of metal site size and metal-metal site distance will be determined; (2) the influence of oxophilicity of the bio-oil HDO sites will be revealed; (3) the impact of support composition will be characterized. To obtain molecular-level understanding of the surface reaction pathways, the bifunctional catalysts will be synthesized with their structures controlled at the nanoscale. Catalyst activity will be measured based on the yields of desired and undesired products from the flow reactor experiments. The dependence of product distribution on (1) the size of the precious metal site, (2) the distance between the DH and HDO sites, (3) metal-oxygen bond strength of the oxophilic metal site, and (4) the compositions of the metal oxide support will be determined. The proposed exploratory research may lead to fundamental understanding of the catalytic geometric and electronic effects on the chemical kinetics of the surface reactions. In addition to training two graduate students, the principal investigators plan to integrate research outcomes into undergraduate and graduate curricula.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.