The dry reforming of methane (DRM) using CO2 has long been considered a viable method for converting methane from geologic or biological sources into syngas, which can then be readily used in the production of a variety of chemicals and particularly liquid fuels that can more readily be shipped via pipeline.Though dry reforming holds great promise, the high temperatures required for the reaction have made it very difficult to find catalysts that exhibit high activity for extended periods. Several factors often lead to the deactivation of these catalysts: the sintering of active metals, the structural rearrangement of the catalyst support and the accumulation of carbon on the catalyst surface. To date, many catalyst materials have been investigated for this reaction, however, in this study we have chosen to develop optimized pyrochlore catalyst materials.Pyrochlores are crystalline oxides having high thermal stability and a general formula of A2B2O7, where A represents a rare-earth metal and B represents a transition metal. Initial experimental efforts by others showed that pyrochlores are active for DRM but the tested catalysts exhibited poor long term stability; nevertheless, more recent data suggests that this trend in deactivation may not be applicable to all pyrochlores. La2Zr2O7(LZ) is a pyrochlore structure which has shown good long term stability, so that efforts have been made to tailor its catalytic properties, showing Rh as a promising dopant to enhance catalytic performance for DRM.In the present work, first principles methods employing Density Functional Theory (DFT) are being used to better understand the reaction mechanism and guide experimental efforts to optimize La2Zr2-xRhxO7 (LRZ) pyrochlores, so as to enhance catalyst activity for syngas production and lower rates of catalyst deactivation.

Optimization of pyrochlore catalysts for the dry reforming of methane

246th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.