(263g) Tailored Redox Catalysts for Methane Partial Oxidation

Methane is commercially used as a feedstock for producing hydrogen and liquid transportation fuels via reforming processes. Although a large number of reforming catalysts have been investigated and commercially utilized, deactivation of reforming catalysts remains as a challenge for the development of more effective catalysts. In the current study, we report a “core-shell” redox catalyst that is both an active reforming catalyst and an effective lattice oxygen (O^2-) donor for methane reforming. Compared to the conventional reforming processes, the proposed redox catalyst is potentially beneficial since the embedded O^2- allows effective oxidation of methane without the presence of external oxidants such as steam or oxygen, avoiding the energy intensive air separation step. The active O^2- also inhibits coke formation, allowing a high syngas selectivity without using steam. After O^2- donation, the oxygen depleted catalyst can be easily regenerated with steam and/or air. A number of redox catalysts composed of a primary metal oxide and mixed ionic-electronic conductor (MIEC), are synthesized, characterized, and tested under redox conditions. Results indicate that the newly developed core-shell redox catalyst is significantly more selective than conventional oxygen carriers for syngas production. It also exhibits better carbon formation resistance and maintained structural/phase integrity.