Catalytic Deoxydehydration of Biomass-Derived Polyols to Olefins

抽象的# 1160219 p。当前位置Friederike C. jentoft将生物质转化为可替代燃料或有用的化学中间体（如烯烃）所需的关键化学转化的特点是在理想情况下有效地去除氧而不大量损失碳。一种方法是采用几个催化转化过程来实现这一目标，允许每个过程在所用催化剂方面进行优化。多元醇是具有多个羟基官能团的分子，在已知的转化过程中很容易从纤维素生物质中获得。俄克拉何马大学的首席研究员Friederike C. Jentoft和Kenneth M. Nicholas提议开发一种新型多相催化剂，将生物质衍生的多元醇底物转化为液相亲水介质。目标反应是脱氧脱水，即通过还原和脱水分别同时除去氧和水。在牺牲还原剂的帮助下，多元醇中两个羟基的净损失可以得到多用途烯烃产品。本项目的主要目标是开发负载型氧化金属配合物作为多元醇脱氧脱水制烯烃产品的催化剂，确定参与这些过程的活性氧化金属种类，并阐明反应机理。项目的成果？化学与生物化学系的Nicholas小组和化学、生物与材料工程学院的Jentoft小组之间的协同互动将促进该目标的实现。这些小组将有机金属化学和均相催化的专业知识与多相催化和光谱学的专业知识结合起来。pi将探索一系列催化剂组成，氧化配合物的候选过渡金属是铼、钼和钒，支持物的候选是活性炭、铈和层状双氢氧化物。将以亚硫酸盐和分子氢为还原剂，在多种条件和溶剂下，测试这些材料对多元醇脱氧脱水的催化活性、选择性和稳定性。催化脱氧脱水过程的关键步骤将通过光谱监测脱氧脱水还原剂和乙二醇与活性负载氧金属配合物的相互作用来阐明。该研究项目的成功实施将：1)建立一种新的、潜在有用的纤维素和乙醇原料的化学转化，用于可持续制备可通过现有工艺进一步转化的增值不饱和产品和中间体；2)对碳水化合物/多元醇类物质、负载型金属氧、实用还原剂和合适的反应介质的化学反应有基本的认识和理解；3)在催化重点学科为本科生、研究生和博士后提供前沿的跨学科教育和技术培训。

ABSTRACT#1160219P.I.: Friederike C. JentoftThe key chemical transformations that are needed in the conversion of biomass into fungible fuels or useful chemical intermediates, such as olefins, are characterized by effectively removing oxygen ideally without significant loss of carbon. One approach would be to achieve this employing several catalytic conversion processes, allowing each to be optimized in terms of catalyst employed. Polyols, molecules with multiple OH functionalities, are easily obtainable from cellulosic biomass in known conversion processes. Principal investigators Friederike C. Jentoft and Kenneth M. Nicholas of the University of Oklahoma are proposing to develop novel, heterogeneous catalysts that will convert biomass-derived polyol substrates in liquid phase, hydrophilic media. The target reaction is a deoxydehydration, that is, oxygen and water will be removed simultaneously by reduction and dehydration, respectively. With the help of a sacrificial reducing agent, the net loss of two OH groups from the polyol can be effected, and a versatile olefinic product is obtained.The primary objectives of this project are to develop supported oxo-metal complexes as catalysts for the deoxydehydration of polyols to olefinic products, to identify the reactive oxo-metal species involved in these processes and to elucidate the reaction mechanism. Achievement of the project?s objective will be facilitated by the synergistic interaction between the Nicholas group in the Department of Chemistry & Biochemistry and the Jentoft group in the School of Chemical, Biological and Materials Engineering. The groups combine expertise in organometallic chemistry and homogeneous catalysis with expertise in heterogeneous catalysis and spectroscopy. The PIs will explore an array of catalyst compositions, with candidate transition metals for the oxo-complexes being rhenium, molybdenum and vanadium, and candidates for supports being activated carbon, ceria, and layered double hydroxides. The catalytic activity, selectivity and stability of these materials for deoxydehydration of polyols will be tested using sulfites and molecular hydrogen as reducing agents and a variety of conditions and solvents. The key steps in the catalytic deoxydehydration processes will be elucidated by spectroscopically monitoring the interaction of deoxydehydration reductants and glycols with active supported oxo-metal complexes. Successful execution of this research project will: 1) establish a new, potentially useful, chemical transformation of cellulosic- and glycolic feedstocks for the sustainable preparation of value-added unsaturated products and intermediates that can be further converted by existing processes; 2) provide fundamental knowledge and understanding of chemical reactions involving carbohydrate/polyol substances, supported metal-oxo species, practical reductants, and suitable reaction media; and 3) supply cutting-edge cross-disciplinary educational and technical training in the key discipline of catalysis for undergraduate and graduate students as well as for postdoctoral researchers.