Alkali metal based selective combustion catalysts

Advances in chemical process technology will be key in reducing the energy use and emissions footprint of petrochemical manufacturing. A recent global chemistry industry technology roadmap identified production of olefinic hydrocarbons (key molecular building blocks for polymer materials) as a standout opportunity in this regard. To that end, the project addresses a novel process scheme for converting light hydrocarbon alkanes to olefins. The process is rooted in a tandem catalytic operation in which alkane dehydrogenation is coupled with selective hydrogen combustion (SHC) to decrease the energy demands, increase olefin yield, and decrease greenhouse gas (GHG) emissions compared to conventional alkane-to-olefin process technology. The technical objectives are supported by a range of educational and outreach initiatives. The project explores catalytic technology based on a new class of non-redox-active alkali metal formulations to selectively combust hydrogen in mixtures with hydrocarbon species. This research will systematically probe the structural and functional evolution of the alkali metal catalyst under high temperature conditions. The research aims to develop an understanding of mechanisms of oxygen activation and selective hydrogen combustion, probe kinetics of the underlying reactions, and ultimately determine the molecular characteristics that enable efficient alkane-to-olefin reaction via selective hydrogen combustion. The scientific objectives will be accomplished by (i) structural and chemical characterization of the alkali metal catalyst formulation using a combination of probe molecule adsorption and reaction studies, near ambient pressure X-ray photoelectron spectroscopy, and diffraction and microscopy methods; and (ii) identification and enumeration of radical species using probe molecule reactions and molecular beam mass spectrometry to determine the potential catalytic role of radical species. Training, education, and outreach efforts as part of this research effort will emphasize the key role of science and engineering in paving next generation technologies for industrial manufacturing and will involve virtual after-school programs, lectures in a massive open online course, training at the undergraduate and graduate level, and development and dissemination of practices suited for safe operation of high temperature reactors. 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.