The Chemistry and Engineering Of C1 Species and The Catalytic Challenges Of Diverse Feedstocks Without C-C Bonds

The recurring cycle of interest in unconventional carbon sources as precursors to chemicals and transportation fuels returns our attention (once again) to the conversion of molecules, such as methane, methanol, and dimethyl ether, lacking C-C bonds.  Such C₁ species, and methane in particular, present specific thermodynamic and kinetic challenges that lead to significant complexity and cost in conversion processes.   Experience and knowledge, gathered at significant expense over the last two decades, has brought to us a clearer view of the inherent bottlenecks.  This talk gathers such learnings and provides some guidance about remaining opportunities,  In doing so, it examines: (i) the kinetic consequences of thermodynamic constraints and the inherent limitations of catalysis in overcoming them; (ii) the preeminence of process simplicity and inexpensive oxidants over the allure of direct conversion processes; (iii) the concepts of kinetic and thermodynamic protection in indirect methane conversion processes; (iv) the coupling of separations and reactions and the cascading of multiple reactions within thermal conduction distances; and (v) the ubiquitous kinetic bottlenecks in forming the first C-C bond in C₁ species.  This guidance is rooted in the long history of conversion technologies and brings together fundamental understanding of the formidable kinetic and thermodynamic constraints with engineering and practical tools designed to overcome them.  The conclusions may seem sobering - as the magnitude of the challenge so warrants - but seek to focus scientific and engineering inquiries within the narrow range of what is possible and practical and to assess ideas of apparent novelty and glamour, as they periodically emerge, within a common context of first principles in kinetics, thermodynamics, and reaction engineering.