SusChEM: Directing the distribution of biomass-derived molecules in porous materials

PI姓名：Susannah L. Scott提案编号：1512228重要化学品和燃料的大规模可持续生产可以通过使用可再生资源如非粮食生物质来实现。 使用多孔固体催化剂在液态水中将生物质衍生的碳水化合物选择性转化为特定化学品部分地通过生物质衍生的碳水化合物分子进入催化剂的多孔结构的分子运动以及产物移出多孔结构来控制。该项目将研究水，催化剂孔结构，碳水化合物和产品之间的相互作用的基础科学，使用高分辨率测量技术探测这些材料的分子相互作用。 研究结果可能会建议如何调整催化过程，以在更短的时间内实现更高的产品收率和选择性。 通过这项研究，学生将有机会在太平洋西北国家实验室的环境分子科学实验室进行高级培训。这项研究的总体目标是了解多孔催化剂中水，生物质衍生的碳水化合物和呋喃基产品之间的相互作用。 以大量生产碳基燃料和化学品所需的规模使用木质纤维素生物质可能涉及在许多化学转化步骤中使用多相催化剂的连续液相加工。 反应介质的各种组分，包括溶剂、反应物、中间体和产物，将在多孔催化剂材料内分配。根据有机溶剂与水结合的混合溶剂系统中的显著效果的观察，假设分子吸收到孔中及其在孔壁上的特异性吸附对选择性具有深远的影响。为了阐明在分子水平上界面限制的性质并量化这些相互作用的程度，该研究将使用固液界面的非原位和原位固态核磁共振（NMR）监测，通过使用专门设计的高温高压魔角旋转探针，评估碳水化合物衍生分子的局部结构及其在多孔材料如沸石、中孔二氧化硅和有机二氧化硅以及碳中的转化率。这一信息将结合量热测量，探测吸收/吸附现象的热力学，和重量测量，以探测其动力学。 作为这项研究的一部分，学生将通过太平洋西北国家实验室的环境分子科学实验室接受先进的核磁共振技术培训。在界面受限物质的行为上获得的知识将识别选择反应物的孔结构，促进所需的反应并排出特定的所需产物，例如呋喃。

PI Name: Susannah L. ScottProposal Number: 1512228The sustainable production of important chemicals and fuels at large scale can be achieved by using renewable resources such as non-food biomass. The selective conversion of biomass-derived carbohydrates to specific chemicals in liquid water using porous solid catalysts is controlled in part by the molecular movement of biomass derived carbohydrate molecules into the porous structure of the catalyst, as well as the movement of products out of the porous structure. This project will study the fundamental science underlying the interactions between water, catalyst pore structure, carbohydrates, and products using high resolution measurement techniques which probe the molecular interactions of these materials. The outcomes of the research may suggest ways to adjust the catalysis process to achieve higher yield and selectivity of products in shorter times. Through this research, students will be given opportunities for advanced training at the Environmental Molecular Sciences Laboratory at Pacific Northwest National Laboratory.The overall goal of this research is to understand the interactions between water, biomass-derived carbohydrates, and furan-based products within porous catalysts. The use of lignocellulosic biomass on the scale required for significant production of carbon-based fuels and chemicals will likely involve continuous liquid-phase processing with heterogeneous catalysts in many of the chemical conversion steps. Various components of the reaction medium, including solvent, reactants, intermediates and products, will partition within the porous catalyst material. Differential absorption of molecules into the pores and their specific adsorption onto the pore walls are hypothesized to have profound consequences for selectivity, based on observations of dramatic effects in mixed solvent systems where an organic solvent is combined with water. To elucidate the nature of the interface confinement at the molecular level and to quantify the extent of these interactions, the research will use ex-situ and in-situ solid-state nuclear magnetic resonance (NMR) monitoring of solid-liquid interfaces, via the use of specially designed high temperature-high pressure magic-angle-spinning probes, to assess local structures of carbohydrate-derived molecules and their rates of transformations in porous materials such as zeolites, mesoporous silicas and organosilicas, and carbons. This information will be combined with calorimetric measurements that probe the thermodynamics of absorption/adsorption phenomena, and gravimetric measurements to probe their kinetics. As part of this research, students will be trained on advanced NMR techniques through the Environmental Molecular Sciences Laboratory at Pacific Northwest National Laboratory. Knowledge gained on the behavior of interface-confined species will identify pore structures that select for reactants, promote desired reactions and expel specific desired products, such as furanics.