CBET-EPSRC: Direct methane conversion into valuable oxygenates via tandem catalysis

随着我国和全球社会向可再生能源的过渡，与有效利用天然气发电、燃料生产和化学制造有关的研究仍将是一项迫切需要。为此，该项目代表了美国和英国研究团队之间的国际合作，通过一种新颖、节能、强化的化学制造工艺，将甲烷（天然气的主要成分）转化为商品化学品。该合作项目将由路易斯安那州立大学的美国团队（nsf资助项目的重点）进行与催化剂设计、合成和表征相关的基础研究，并结合卡迪夫催化研究所（CCI）与伦敦帝国理工学院（由工程和物理科学研究委员会EPSRC资助）合作进行的相关催化剂和反应工程研究。除了技术目标之外，美国项目将通过LSU本科生研究经验项目和LSU高中暑期研究（HSSR）项目支持学生主导的研究，该项目针对代表性不足的群体。当今催化和反应工程面临的最重大挑战之一是将甲烷转化为高价值化学品。该项目探索了一种新的组合催化剂设计和工程方法，以催化串联反应将甲烷转化为关键的化学中间体，即乙酸和甲醇。该方法是基于观察到负载型AuPd合金纳米颗粒可以通过氢（H2）和氧（O2）的直接合成路线生成过氧化氢，并可用于引发串联催化反应。中心愿景是开发串联三金属催化剂设计，使过氧化氢形成的催化剂功能接近羰基化和部分氧化甲醇/乙酸产物的催化剂功能。串联催化剂方法还得到了一个复杂的微通道单片反应器设计的进一步辅助，该设计与基于Taylor流动的液体和气体流动机制相结合，使气体种类沿着浓度梯度分离，使平衡向所需产物转移。该项目建立在美国和英国研究团队（以及英国行业合作伙伴）之间现有的合作研究基础上，他们拥有互补的专业知识，将催化剂合成、表征、反应工程和实施专业知识的独特组合结合在一起。特别是路易斯安那州立大学的团队，在催化剂合成、表征和评估方面增加了关键的专业知识。表征组件利用了LSU内部同步加速器设施（LSU- camd）的x射线光谱分析能力，以及通过最近获得的最先进的透射电子显微镜进行原子分辨率成像和元素映射。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。

Research related to efficient utilization of natural gas for energy generation, fuels production and chemical manufacturing will remain a critical need as our nation and the global community transition to renewable energy. To that end, this project represents an international effort between research teams in the U.S. and the United Kingdom (UK) to convert methane (the chief component of natural gas) to commodity chemicals via a novel, energy-efficient, intensified chemical manufacturing process. The collaborative effort will feature fundamental research related to catalyst design, synthesis, and characterization by the U.S. team at Louisiana State University (the focus of this NSF-funded project), combined with related catalyst and reaction engineering research by the Cardiff Catalysis Institute (CCI) in collaboration with Imperial College London (funded by the Engineering and Physical Sciences Research Council, EPSRC). Beyond the technological objectives, the U.S. project will support student-led research through the LSU Research Experiences for Undergraduates program together with the LSU High School Summer Research (HSSR) program targeting underrepresented groups. One of the most significant catalysis and reaction engineering challenges faced today is the conversion of methane to higher-value chemicals. The project explores a novel combined catalyst design and engineering approach to catalyze tandem reactions to convert methane to key chemical intermediates, namely acetic acid and methanol. The approach is based on the observation that supported AuPd alloy nanoparticles can form hydrogen peroxide by a direct synthesis route from hydrogen (H2) and oxygen (O2), and this can be used to initiate a tandem catalytic reaction. The central vision is the development of tandem trimetallic catalyst design that places the catalyst functionality for hydrogen peroxide formation near the catalyst functionality for carbonylation and partial oxidation to methanol/acetic acid products. The tandem catalyst approach is further aided by a sophisticated micro-channel monolithic reactor design coupled to Taylor flow-based regimes of liquid and gas flow that enable separation of gas species along concentration gradients that shift equilibrium towards the desired products. The project builds on existing collaborative research between the U.S. and UK research teams (together with UK industry partners) who have the complementary expertise needed to bring together a unique combination of catalyst synthesis, characterization, and reaction engineering and implementation expertise. The LSU team, in particular, adds critical expertise in catalyst synthesis, characterization, and evaluation. The characterization component takes advantage of X-ray spectroscopic analysis capabilities of LSU’s in-house synchrotron facility (LSU-CAMD) together with atomic resolution imaging and elemental mapping via a recently acquired state-of-the-art transmission electron microscope.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.