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

1508048Vohs, John m .木质素基生物质的生物精炼产生含氧芳香族化合物，这些化合物必须通过氢脱氧（HDO）进一步处理以产生更高价值的芳香族化合物。该研究将包括分子水平上对几种含氧芳烃在双金属催化剂（从单晶到负载催化剂）上的吸附和反应的研究。由此产生的见解将有助于发现和开发催化剂，将含氧芳香族化合物转化为有用的燃料和化学品。这项工作还将训练本科生和研究生掌握与实现可持续能源和环境未来有关的技能。双金属催化剂由一种10族金属（Ni, Pd, Pt）和另一种亲氧金属（如Fe或Zn）组成，将根据先前在醛和醛糖HDO中的HDO活性的演示来选择。具体来说，该提案将研究由于添加第二种更亲氧的金属（例如，Fe或Zn）而导致的金属d带的变化如何影响芳香环与催化剂表面的相互作用，以及这在降低不良环氢化的总体活性中所起的作用。该研究还将研究亲氧金属在为芳香氧化物中的氧原子提供特定结合位点方面的作用，以及这些位点在HC=O、C-OH和C-O- c基团中促进C-O键断裂方面的作用。除了单晶研究外，还将制备高表面积负载的双金属催化剂，并对吸附物质进行光谱表征，并在气相流反应器中进行评估，以获得反应动力学和对所需产物的选择性。该提案明确解决了整个生物质精炼计划中的关键步骤（HDO）。因此，它将提供有助于发展生物质精炼方案的基本见解，从而使木质纤维素生物质转化更接近于经济上可实现的过程，并为可再生能源和化学品带来随之而来的好处。该项目还将培养能源转换、多相催化和反应工程领域的研究生和本科生，这些都是美国石化行业急需的技能。

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.