Collaborative Research: Understanding and manipulating the solvent microenvironment for selective, catalytic amination of renewable oxygenates

生物质精炼的最初步骤包括将原料分解成含有构建块化学物质混合物的生物原油。在溶剂和固体催化剂的帮助下，通常在液相中，构建块化学品可以进一步精炼成更高价值的产品。该项目将研究其中一种基本化学物质3-羟基丁内酯（3HBA）向几种高价值化学物质的转化。将理论分析和实验方法相结合，了解溶剂如何影响催化剂的性能，促进3HBA转化为所需产品。这项研究的结果可以更广泛地应用于其他生物基化学品，以支持与向可再生化学品生产过渡相关的日益增长的生物精炼工业。该项目将有助于培养一支训练有素的生物质加工专家队伍，同时也将增强美国在生物化学品制造方面的技术优势。多相催化研究的一个主要目标是确定活性位点，并了解它们如何与反应物、产物和整体环境相互作用，以促进化学转化。虽然大多数催化剂研究的重点是催化剂的发现，但从重新设计中获益最多的往往是体反应环境。近年来，随着生物质的液相催化处理的发展，对异构催化中溶剂化效应的关注得到了扩展。在这种转变的推动下，该项目专注于开发合理设计溶剂系统所需的科学基础，以催化处理可再生氧合物。具体而言，本研究旨在了解溶剂微环境的性质如何影响钌（Ru）催化剂在3-HBA还原胺化过程中生成2-氨基-3-羟基四氢呋喃和3-氨基四氢呋喃的活性和选择性。计算和实验研究的结合是围绕(1)最先进的密度泛函数理论计算，(2)加速复杂反应网络研究的机器学习工具，(3)各种实验反应条件下的微动力学反应器建模，(4)气相催化剂评价和动力学同位素效应研究，(5)水、乙醇、1,4-二恶烷和环己烷凝聚相催化剂评价，(6)通过贝叶斯统计分析将实验数据与计算模型进行系统关联。提出了一个迭代研究循环，实验观察导致假设，激发新的计算，而计算模型将使实验结果合理化并指导新的研究。该研究项目包括本科生外展，研究成果将整合到雪城大学和南卡罗来纳大学的本科生和研究生选修课以及核心化学工程课程中。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The initial steps of biomass refining involve breakdown of the raw material to a biocrude oil containing a mixture of building block chemicals. The building block chemicals can be further refined to higher value products, often in the liquid phase, with the aid of a solvent and a solid catalyst. This project will investigate the transformation of one of those building block chemicals, 3-hydroxybutryolactone (3HBA), to several higher-value chemicals. Theoretical analysis and experimental methods will be combined to understand how the solvent influences the performance of the catalyst in promoting conversion of 3HBA to the desired products. Results of the study can be applied more generally to other bio-based chemicals to support a growing bio-refining industry relevant for the transition to renewable chemical production. The project will contribute to a highly trained workforce of experts in biomass processing, while also adding to U.S. technical prominence in biomanufacturing of chemicals. A major goal of heterogeneous catalysis research is to identify active sites and to understand how they interact with reactants, products, and the bulk environment to facilitate chemical transformations. While most catalyst studies focus on catalyst discovery, it is often the bulk reaction environment that benefits most from redesign. The focus on solvation effects in heterogeneous catalysis has recently expanded with the trend toward liquid-phase, catalytic processing of biomass. Motivated by this shift, the project focuses on developing the scientific foundations needed for the rational design of solvent systems for catalytically processing renewable oxygenates. Specifically, the proposed research aims at understanding how the nature of the solvent microenvironment impacts activity and selectivity of ruthenium (Ru) catalysts during reductive amination of 3-HBA to form 2-amino-3-hydroxytetrahydrofuran and 3-aminotetrahydrofuran. The proposed combination of computational and experimental research is structured around (1) state-of-the-art density functional theory calculations, (2) machine learning tools for accelerating complex reaction network investigation, (3) microkinetic reactor modeling under various experimental reaction conditions, (4) vapor phase catalyst evaluation and kinetic isotope effect studies, (5) catalyst evaluations in condensed phases of water, ethanol, 1,4-dioxane, and cyclohexane, and (6) systematic correlation of experimental data with computational models through Bayesian statistical analysis. An iterative research loop is proposed, with experimental observations leading to hypotheses that motivate new computations, while computational models will rationalize experimental findings and guide new investigations. The research program includes undergraduate outreach, and research results will be integrated into undergraduate and graduate electives and the core chemical engineering curriculum at both Syracuse University and the University of South Carolina.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.