SusChEM: Collaborative Research: Surface Reaction of Oxygenates on Lewis Acidic Metal Oxides

SusChEM：合作研究：路易斯酸性金属氧化物上氧化物的表面反应

• 批准号: 1705444
• 负责人: Carsten Sievers
• 金额: $ 29.95万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1705444&HistoricalAwards=false
• 关键词: SusChEM; Collaborative; Research; Surface; Reaction

The overall goal of the project is to enable the design of Lewis acid catalysts for conversion of sugars (readily obtained from fermentation of biorenewables) to value-added chemicals. Metal oxide catalysts, such as titanium dioxide and molybdenum oxides, are active for a number of reactions of sugars, but understanding is lacking regarding relationships between the composition and structure of various catalysts and the products they produce. The project will identify the reasons why different catalysts produce different products, and thus facilitate the design of catalysts that are optimized for the production of specific target compounds, including high-value biorenewable products such as ethylene glycol and lactic acid. The project will utilize low-cost catalyst materials that will pave the way to economically viable routes for enabling sustainable production of valuable chemical feedstocks.Recent work has shown that the relative rates for key isomerization and retro aldol pathways are strongly influenced by the catalyst composition. A combination of surface science experiments on model surfaces, spectroscopic and kinetic studies of high-surface area oxides, and density functional theory calculations will be employed to identify how surface structure and composition affect the rates of individual elementary reaction steps. Specifically, the research will focus on how elementary reactions for sugar conversion are affected by various surface properties, including electronic properties (such as Lewis acid strength and orbital filling) and geometric factors (such as steric hindrance or proximity of cooperative active centers). Isolation of key elementary steps, which include activation or formation of O-H, C-H, C-O, and C-C bonds in carbohydrates, will be enabled by studying the surface reactions of appropriate probe reactants across the research approaches. Experimental surface science studies will provide new information on elementary step barriers and reaction intermediates on different surfaces. Computation will assist in mechanism development, but more importantly will be used to assess how trends in surface intermediate adsorption energies and barriers for their reactions are related to electronic properties. Operando spectroscopy investigations will provide a new understanding of how complexities, such as non-ideal surfaces and the presence of a solvent, perturb the structure and stability of surface intermediates, providing key feedback for refinement of reaction models that will ultimately be used to design improved catalysts. The project will build on the investigators' track record of training graduate and undergraduate students including students from traditionally underrepresented groups. The project will allow both PhD and undergraduate students to participate in rotations among the different laboratories to develop an ability to address the same overall problem from different angles. Community outreach activities include engagement with an Atlanta-area museum and programs for K-12 students.

该项目的总体目的是使刘易斯酸催化剂的设计用于糖的转化（从生物可生的发酵物中易于获得）到增值化学物质。 金属氧化物催化剂，例如二氧化钛和钼氧化物，对糖的多种反应具有活性，但是对于各种催化剂的组成和结构之间的关系及其产生的产物之间的关系缺乏理解。 该项目将确定不同催化剂生产不同产品的原因，从而促进了针对特定靶化合物的生产（包括高价值生物可生物可生产物）（例如乙烯甘油和乳酸）进行优化的催化剂的设计。 该项目将利用低成本的催化剂材料，为实现有价值的化学原料的可持续生产铺平道路。 将采用在模型表面，高表面区域氧化物的光谱和动力学研究以及密度功能理论计算上的表面科学实验的组合，以确定表面结构和组成如何影响个体基本反应步骤的速率。 具体而言，该研究将集中于糖转化的基本反应如何受到各种表面特性的影响，包括电子特性（例如刘易斯酸强度和轨道填充）和几何因素（例如，合作活动中心的空间障碍或接近性）。 将通过研究研究方法中适当的探针反应物的表面反应来启用关键基本步骤的分离，包括碳水化合物中O-H，C-H，C-O和C-C键的激活或形成。 实验表面科学研究将提供有关不同表面上基本步骤屏障和反应中间体的新信息。 计算将有助于机理的发展，但更重要的是，将用于评估表面中间吸附能的趋势如何与它们的反应有关的障碍与电子特性有关。 Operando光谱研究将提供新的理解，以了解复杂性，例如非理想表面和溶剂的存在，扰乱表面中间体的结构和稳定性，为改进反应模型提供了关键的反馈，这些反应模型最终将用于设计改进的催化剂。 该项目将基于调查人员的培训毕业生和本科生的记录，包括传统代表性不足的团体的学生。 该项目将允许博士学位和本科生参与不同实验室之间的轮换，以发展从不同角度解决相同总体问题的能力。 社区外展活动包括与亚特兰大地区博物馆的订婚以及针对K-12学生的计划。

项目成果

Supported Molybdenum Oxides for the Aldol Condensation Reaction of Acetaldehyde

• DOI: 10.1016/j.jcat.2022.03.002
• 发表时间: 2022-03
• 期刊: Journal of Catalysis
• 影响因子: 7.3
• 作者: M. Rasmussen;Sean Najmi;Giada Innocenti;A. Medford;Carsten Sievers;J. Will Medlin

In‐situ IR Spectroscopy Study of Reactions of C3 Oxygenates on Heteroatom (Sn, Mo, and W) doped BEA Zeolites and the Effect of Co‐adsorbed Water

• DOI: 10.1002/cctc.202001424
• 发表时间: 2020-11
• 期刊: ChemCatChem
• 影响因子: 4.5
• 作者: Sean Najmi;Jungseob So;E. Stavitski;William P. McDermott;Yimeng Lyu;S. Burt;Ive Hermans;D. Sholl;Carsten Sievers

Pretreatment Effects on the Surface Chemistry of Small Oxygenates on Molybdenum Trioxide

• DOI: 10.1021/acscatal.0c01992
• 发表时间: 2020-08-07
• 期刊: ACS CATALYSIS
• 影响因子: 12.9
• 作者: Najmi, Sean;Rasmussen, Mathew;Sievers, Carsten
• 通讯作者: Sievers, Carsten

Continuous Liquid-Phase Upgrading of Dihydroxyacetone to Lactic Acid over Metal Phosphate Catalysts

• DOI: 10.1021/acscatal.0c03761
• 发表时间: 2020-10-16
• 期刊: ACS CATALYSIS
• 影响因子: 12.9
• 作者: Innocenti, Giada;Papadopoulos, Eleni;Sievers, Carsten
• 通讯作者: Sievers, Carsten