SusChEM: Surface Active Site Design for Selective Deoxygenation

SusChEM：用于选择性脱氧的表面活性位点设计

• 批准号: 1464979
• 负责人: Will Medlin
• 金额: $ 51.88万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1464979&HistoricalAwards=false
• 关键词: SusChEM; Surface; Active; Site; Design

Many chemical processes require the ability to make or break carbon-oxygen bonds in a compound without affecting other bonds. The conversion of biomass to fuels and chemicals requires carbon-oxygen bond dissociation (or "deoxygenation") reactions to improve the compatibility of biomass-derived compounds with the existing refining infrastructure. Unfortunately, catalysts that are effective for deoxygenation also often catalyze other, undesired reactions that lead to the loss of carbon. The ability to design solid materials that specifically remove oxygen from a feedstock is thus a goal of modern catalysis research. In this project, Dr. J. Will Medlin of the University of Colorado Boulder is investigating how interactions between oxygen-containing reactants on catalyst surfaces can be tuned to allow for specific removal of oxygen from a feedstock. Dr. Medlin is also investigating the role that catalyst nanostructure plays in favoring oxygen removal reactions over those that remove carbon. The project integrates scientific outreach and training within the research program. These outreach activities include summer research opportunities for undergraduate students, as well as expansion of an annual chemistry and chemical engineering "Field Day" activity that is focused on hands-on science experiments for middle school students. With funding from the Chemical Catalysis Program of the Chemistry Division, Dr. J. Will Medlin of the University of Colorado Boulder is developing an understanding of the mechanism for deoxygenation reactions of alcohols on metal surfaces. Selective activation of carbon-oxygen bonds is important in many applications, including the conversion of biomass-derived compounds to fuels and chemicals. It is especially important to identify catalysts that are selective for carbon-oxygen bond activation, since cleavage of carbon-carbon bonds generally results in carbon loss and reduced efficiency. Although certain metal surfaces have been identified as being unusually active and selective for deoxygenation, the relationship between surface properties and deoxygenation performance is not well understood, hampering efforts to design improved catalysts. In this project, Dr. Medlin is employing a combination of experimental studies using model surfaces, density functional theory calculations, and experiments with supported catalysts to systematically investigate factors that have previously been associated with high deoxygenation selectivity. In this project, isotope tracing studies are employed to systematically investigate the mechanism for the critical hydrogen transfer step during deoxygenation. Deoxygenation selectivity and kinetics are measured for a variety of palladium surfaces to identify the geometric structures associated with efficient deoxygenation. The goal of this project is to identify simple catalyst descriptors that can inform design of efficient catalysts. This project emphasizes STEM education through the research training of students across multiple levels, as well as through an annual "Field Day" activity for middle school students organized by Dr. Medlin's group.

许多化学过程需要能够在化合物中形成或破坏碳-氧键而不影响其他键。 将生物质转化为燃料和化学品需要碳-氧键解离（或“脱氧”）反应，以提高生物质衍生化合物与现有炼油基础设施的相容性。 不幸的是，有效脱氧的​​催化剂也常常催化其他不期望的反应，导致碳损失。 因此，设计专门从原料中去除氧气的固体材料的能力是现代催化研究的目标。在该项目中，科罗拉多大学博尔德分校的 J. Will Medlin 博士正在研究如何调整催化剂表面上的含氧反应物之间的相互作用，以实现从原料中特定去除氧。 梅德林博士还在研究催化剂纳米结构在促进除碳反应而不是除碳反应方面所起的作用。该项目将科学推广和培训纳入研究计划。 这些外展活动包括为本科生提供夏季研究机会，以及扩大每年一度的化学和化学工程“实地日”活动，该活动的重点是为中学生进行科学实践实验。 在化学系化学催化项目的资助下，科罗拉多大学博尔德分校的 J. Will Medlin 博士正在深入了解金属表面上醇类脱氧反应的机制。碳-氧键的选择性活化在许多应用中都很重要，包括将生物质衍生的化合物转化为燃料和化学品。 识别对碳-氧键活化具有选择性的催化剂尤其重要，因为碳-碳键的断裂通常会导致碳损失和效率降低。 尽管某些金属表面已被认为对脱氧具有异常活性和选择性，但表面性质和脱氧性能之间的关系尚不清楚，这阻碍了设计改进催化剂的努力。 在该项目中，Medlin 博士结合使用模型表面、密度泛函理论计算和负载催化剂实验的实验研究来系统地研究以前与高脱氧选择性相关的因素。在该项目中，采用同位素示踪研究来系统地研究脱氧过程中关键的氢转移步骤的机制。测量各种钯表面的脱氧选择性和动力学，以确定与有效脱氧相关的几何结构。 该项目的目标是确定简单的催化剂描述符，为高效催化剂的设计提供信息。该项目通过对学生进行多个层次的研究培训以及每年由 Medlin 博士团队为中学生组织的“Field Day”活动来强调 STEM 教育。