Catalytic Hydrodeoxygenation of Sugar Acids to Dicarboxylic Acids

将进行探索性研究，以评估从可再生碳源（如木质纤维素生物质）生产二羧酸的潜在变革性催化剂技术的可行性。 这些酸的当前工业方法-广泛用于聚合物、药物、溶剂、纺织品和塑料的生产-依赖于来自化石来源的石化原料，并且利用相对苛刻的条件和能源密集型分离。生物质来源可能提供更直接的合成途径，同时有助于能源的可持续性。 该研究将解决与碳结构中含氧基团的特定化学反应相关的挑战，同时还将探索减少对昂贵贵金属催化剂组分需求的催化剂配方。 最近，人们对从可再生资源生产二羧酸的兴趣激增，主要是通过葡萄糖发酵或通过进一步加工来自天然生物加工的废副产物，如来自酿酒的酒石酸。具体而言，该研究将针对两个模型酒石酸反应：脱氧脱水为马来酸和加氢脱氧为琥珀酸，两者都在常用溶剂中进行。该研究将解决两个首要目标，1）一种非均相催化剂的开发组成的三氧化二镓支持促进的二氧化铈，和2）的三氧化二镓催化剂的催化性能的研究，以各种方式制备，邻二醇在酒石酸的脱氧脱水和加氢脱氧。 该研究的一个关键方面是在镓促进的二氧化铈上负载氧化铈可以在多大程度上提高催化剂的稳定性，同时消除对常见贵金属组分如钯或铱的需要，从而为更耐用和更低成本的催化剂铺平道路。 所提出的催化剂配方的成功证明取决于镓促进的氧化铈载体可以稳定分离的单体氧化铈物质（具有不同氧化态）并实现氢气的容易解离的程度，这是连续氢化反应和活性金属中心再生所需的。 这两种功能通常通过在催化剂合成中引入钯来实现。 数据表明，消除昂贵的贵金属组分的可能性，同时稳定的活性碳物种，将开辟一条道路，以转化催化剂技术，从生物可再生的碳原料生产二羧酸。 该研究还包括一项教育计划，旨在增加本科西班牙裔妇女参与研究，并加强PI机构在纳米技术，工程材料和可再生能源等关键领域的本科课程。

Exploratory research will be conducted to assess the feasibility of potentially transformative catalyst technology for manufacturing dicarboxylic acids from renewable sources of carbon such as lignocellulosic biomass. Current industrial processes for these acids - which are used widely in the production of polymers, pharmaceuticals, solvents, textiles, and plastics - rely on petrochemical feedstocks derived from fossil sources, and utilize relatively harsh conditions and energy-intensive separations. Biomass sources potentially offer a more direct synthesis route while contributing to energy sustainability. The study will address challenges associated with specific chemical reactions at oxygen-containing groups in the carbon structure, while also exploring catalyst formulations that decrease the need for expensive precious metal catalyst components. Recently, interest has surged in the production of dicarboxylic acids from renewable sources, mainly via fermentation of glucose or through further processing of waste byproducts from natural bio-processing such as tartaric acid from wine-making. Specifically, the study will target two model tartaric acid reactions: deoxydehydration to maleic acid and hydrodeoxygenation to succinic acid, both carried out in commonly available solvents. The study will address two overarching objectives, 1) the development of a heterogeneous catalyst comprised of rhenium oxide supported on gallium-promoted cerium dioxide, and 2) a study of the catalytic performance of the rhenium oxide catalysts, prepared in various ways, on the deoxydehydration and hydrodeoxygenation of vicinal diols in tartaric acid. A key aspect of the study is the extent to which supporting the rhenium oxide on the gallium-promoted cerium dioxide can enhance the stability of the catalyst while eliminating the need for common precious metal components such as palladium or iridium, thus paving the way for more durable and lower cost catalysts. Successful demonstration of the proposed catalyst formulation depends on the extent to which the gallium-promoted cerium oxide support can both stabilize isolated monomeric rhenium oxide species (of varying oxidation state) and achieve the facile dissociation of hydrogen gas, as required for the sequential hydrogenation reactions and for regeneration of the active rhenium site. Both of those functions are typically achieved through the incorporation of palladium in the catalyst synthesis. Data suggesting the possibility of eliminating the expensive noble metal component, while stabilizing the active rhenium species, would open a path to transformative catalyst technologies for producing dicarboxylic acids from biorenewable carbon feedstocks. The study also includes an education plan aimed at increasing the involvement of undergraduate Hispanic women in research, and enhancing undergraduate curricula at the PI's institution in key areas related to nanotechnology, engineering materials, and renewable energy.