Bifunctional Catalysts for Selective Hydrogenation of Biomass Derivatives: Furfural Hydrogenation over Pt-Sn Supported on Titania

生物质化学转化为燃料的过程提供了可再生能源，减少了对化石燃料的依赖，并为农产品和生物制品提供了新的市场。生物质重整的一个主要挑战是脱氧，这降低了生物质衍生物的长期稳定性。需要新的催化剂来促进生物质转化为可使用的燃料以及高价值的化学品。在这项研究项目中，南卡罗来纳大学的Donna A.Chen博士和德克萨斯大学奥斯汀分校的Graeme Henkelman博士正在研究由两种不同金属组成的催化剂，这些催化剂的目标是与生物质衍生物中不同官能团相关的特定化学反应。这两名研究人员还参与了促进对各级学生进行科学教育和培训的外联活动。与当地小学合作，陈博士正在开发直接适合学生科学课程的动手化学教程和演示。亨克尔曼博士领导了一项倡议，招募大学一年级学生参加积极的研究项目，目标是来自历史上在科学界代表性较低的背景的学生。在化学系化学催化计划的资助下，南卡罗来纳大学的Donna A.Chen博士和德克萨斯大学奥斯汀分校的Graeme Henkelman博士开发了选择性催化剂，用于转化来自纤维素生物质重整的高官能化分子。研究了氧化物负载的双金属催化剂，如铂-锡，用于糠醛的选择性加氢，以生产粘合剂、水泥和涂料。铂-锡表面的双功能性质应该允许高活性的C=O键的选择性氢化，同时抑制其他氢化途径。另一方面，铂和氧化物载体之间的强相互作用有望提高选择性并防止碳污染。陈博士研究了在超高真空(UHV)中制备的、定义良好的铂-锡/二氧化钛表面模型。使用各种表面科学技术对这些模型表面进行了表征。催化活性研究是在直接耦合到特高压反应室的微反应器中进行的。Henkelman博士使用密度泛函理论对被支持的双金属粒子进行建模，以了解活性、选择性和稳定性，并预测哪些双金属组合有望显示出理想的性能。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The chemical transformation of biomass into fuels is a process that provides a renewable source of energy, decreases dependence on fossil fuels, and provides new markets for agricultural products and bioproducts. A major challenge in the reforming of biomass is the removal of oxygen, which decreases the long-term stability of biomass derivatives. New catalysts are needed to facilitate the conversion of biomass into useable fuels, as well as high-value chemicals. In this research project, Dr. Donna A. Chen of the University of South Carolina and Dr. Graeme Henkelman of the University of Texas at Austin are studying catalysts composed of two different metals that target specific chemical reactions associated with the different functional groups in biomass derivatives. Both researchers are also engaged in outreach activities that promote the scientific education and training of students of all levels. In conjunction with local elementary schools, Dr. Chen is developing hands-on chemistry tutorials and demonstrations that fit directly into the students' science curriculum. Dr. Henkelman leads an initiative that recruits freshman college students into active research programs and targets students who are from backgrounds that are historically underrepresented in science. With funding from the Chemical Catalysis Program of the Chemistry Division, Dr. Donna A. Chen from the University of South Carolina and Dr. Graeme Henkelman from the University of Texas at Austin develop selective catalysts for the conversion of highly functionalized molecules derived from cellulosic biomass reforming. Oxide-supported bimetallic catalysts such as Pt-Sn are investigated for the selective hydrogenation of furfural for the subsequent production of adhesives, cements, and coatings. The bifunctional nature of the Pt-Sn surfaces should allow selective hydrogenation of the C=O bond with high activity while inhibiting other hydrogenation pathways. On the other hand, strong interactions between Pt and the oxide support are expected to improve selectivity and prevent carbon fouling. Dr. Chen studies model, well-defined Pt-Sn/titania surfaces prepared in ultrahigh vacuum (UHV). These model surfaces are characterized using a variety of surface science techniques. Catalytic activity studies are conducted in a microreactor directly coupled to the UHV chamber. Dr. Henkelman models the supported bimetallic particles using density functional theory to understand activity, selectively and stability, and to predict which bimetallic combinations are expected to exhibit desirable properties.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.