UNS: Mechanistic Studies of Hydrodeoxygenation of Lignin-Derived Aromatic Oxygenates over Bimetallic Catalysts

1508048Vohs，John M.木质素生物质的生物精炼会产生含氧芳香化合物，这些化合物必须通过加氢脱氧(HDO)进一步处理，才能产生更高价值的芳香化合物。这项研究将从分子水平上研究几种含氧芳烃在从单晶到负载型催化剂的双金属催化剂上的吸附和反应。由此产生的洞察力将有助于发现和开发将含氧芳香化合物转化为有用燃料和化学品的催化剂。这项工作还将培训本科生和研究生与实现可持续能源和环境未来相关的技能。由10族金属(镍、钯、铂)和第二种更亲氧的金属(如铁或锌)组成的双金属催化剂将基于先前在醛和醛糖中的HDO活性的证明而被选择。具体地说，该提案将调查由于添加第二个更亲氧的金属(例如铁或锌)而导致的金属d带的变化如何影响芳环与催化剂表面的相互作用，以及这在降低不良环加氢的整体活性方面所起的作用。这项研究还将考察亲氧金属在为芳香族含氧物中的氧原子提供特定结合位置方面的作用，以及这些位置在促进HC=O、C-OH和C-O-C基团中C-O键断裂方面的作用。除了单晶研究外，还将制备高比表面积负载型双金属催化剂，并对吸附物种进行光谱表征，并在气相流动反应器中进行评价，以获得反应动力学和对所需产物的选择性。该提案明确涉及整个生物质精炼计划中的一个关键步骤(HDO)。因此，它将提供基本的见解，帮助制定生物质精炼计划，从而使木质纤维素生物质转化更接近经济上可实现的过程，从而为可再生能源和化学品带来好处。该项目还将培训能源转换、多相催化和反应工程领域的研究生和本科生，这些技能是美国石化行业非常需要的技能。

1508048Vohs, John M.Bio-refining of lignin-based biomass results in production of oxygenated aromatic compounds that must be further processed by hydrodeoxygenation (HDO) to produce higher-value aromatic compounds. The study will involve molecular-level investigation of the adsorption and reaction of several oxygenated aromatics on bimetallic catalysts ranging from single crystals to supported catalysts. The resulting insight will aid the discovery and development of catalysts that convert oxygenated aromatic compounds to useful fuels and chemicals. The work will also train students at both the undergraduate and graduate levels in skills relevant to the realization of a sustainable energy and environmental future. Bimetallic catalysts composed of a group-10 metal (Ni, Pd, Pt) and a second more oxyphilic metal, such as Fe or Zn, will be chosen based on previous demonstration of HDO activity in aldehyde and aldose HDO. Specifically, the proposal will investigate how changes in the metal d-band resulting from the addition of a second more oxyphilic metal (e.g., Fe or Zn) influence the interaction of aromatic rings with the catalyst surface and the role this plays in decreasing overall activity for undesirable ring hydrogenation. The study will also examine the role of the oxyphilic metal in providing specific binding sites for the oxygen atoms in the aromatic oxygenates and the role of these sites in facilitating C-O bond cleavage in HC=O, C-OH, and C-O-C groups. In addition to the single crystal studies, high-surface-area supported bimetallic catalysts will be prepared and subjected to spectroscopic characterization of adsorbed species, and evaluated in a gas-phase flow-reactor to obtain reaction kinetics and selectivity to desired products. The proposal clearly addresses a critical step (HDO) in the overall biomass refining scheme. As such, it will provide fundamental insight that will aid the development of biomass refining schemes and thereby move lignocellulosic biomass conversion closer to an economically realizable process, with attendant benefits for renewable energy and chemicals. The project will also train both graduate and undergraduate students in the fields of energy conversion, heterogeneous catalysis, and reaction engineering - skills highly sought by the U.S. petrochemical industry.