Selective Production of Carbon Monoxide via Methane Oxychlorination over Vanadyl Pyrophosphate

摘要

A catalytic process is demonstrated for the selective conversion of methane into carbon monoxide via oxychlorination chemistry. The process involves addition of HCl to a CH4-O-2 feed to facilitate C-H bond activation under mild conditions, leading to the formation of chloromethanes, CH3Cl and CH2Cl2. The latter are oxidized in situ over the same catalyst, yielding CO and recycling HCl. Amaterial exhibiting chlorine evolution by HCl oxidation, high activity to oxidize chloromethanes into CO, and no ability to oxidize CO, is therefore essential to accomplish this target. Following these design criteria, vanadyl pyrophosphate (VPO) was identified as an outstanding catalyst, exhibiting a CO yield up to approximately 35% at 96% selectivity and stable behavior. These findings constitute a basis for the development of a process enabling the on-site valorization of stranded natural-gas reserves using CO as a highly versatile platform molecule.