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

Louisiana State University, Baton Rouge LA

Investigators

Abstract

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.