“Soft” oxidative coupling of methane to ethylene: Mechanistic insights from combined experiment and theory
Shanfu Liu, Sagar Udyavara, Chi Zhang, Matthias Peter, Tracy L. Lohr, Vinayak P. Dravid, Matthew Neurock, Tobin J. Marks
Abstract
Significance Highly abundant methane is vastly underutilized as a feedstock for chemicals and fuels reflecting its inertness. One seemingly attractive approach to methane utilization would be direct catalytic oxidative coupling of methane (OCM) with O 2 to produce ethylene, a valuable chemical feedstock. However, the exothermicity leads largely to nonselective oxidation to CO 2 , a challenge that remains despite decades of research. These results raise the intriguing question of whether the “softer” isoelectronic oxidant, S 2 , might achieve analogous SOCM with acceptable selectivity. Here, we report a combined experimental and computational investigation of the SOCM reaction mechanism, comparing and contrasting with that of conventional OCM. We find that SOCM shows promising selectivity to ethylene and proceeds via a very different pathway than does OCM.