The goal of the research is to uncover electrocatalytic means of methane activation in order to provide insight into the detailed mechanism of partial oxidation of methane and in the origin of the Non-Faradayic Electrochemical Modification of Catalytic Activity (NEMCA).
In this project methane upgrading to dimerized products and to synthesis gas will be investigated using a combined approach in which two types of solid oxide membranes are applied.
1. Proton and oxygen ion conducting solid electrolytes.
This part of the project aims at the application of solid electrolyte cells in methane upgrading schemes. The intrinsic reactivity or selectivity of catalyst electrodes is modified by using the technique of electrochemical oxygen (hydrogen) pumping using an external power source. Tasks of the work programme include the study of methane electrocatalytic dehydrogenation to ethane and ethene over silver electrodes using a proton-conducting electrolyte, e.g. Yb-doped SrCeO3 (SCY) and the study of synthesis gas formation over iron electrodes using an oxygen ion conducting electrolyte, Y2O3-doped ZRO2 (YSZ). The methane coupling study will be carried out in a divided (double-chamber) and an undivided (single-chamber) cell configuration.
2. Mixed ionic-electronic conductors.
This part of the project aims at the application of mixed ionic-electronic conductors as oxygen separating membranes in methane upgrading schemes, particular attention being given to oxidative methane coupling. The major issue is that an oxygen pressure differential is imposed across the semipermeable membrane for selective feeding of oxygen to the catalyst surface, without involving metal electrodes or conductive wires. The oxide membrane may be adapted for application by deposition of a thin porous (conventional) catalyst overlayer on the side of the membrane which is exposed to the CH4 containing feed stream. The work programme also covers the selection of candidate membrane materials by regarding their -oxygen semipermeability, - high temperature stability, -activity towards homomolecular and heterogeneous oxygen exchange and -intrinsic catalytic activity in partial oxidation to C2 hydrocarbons and possibly methanol or formaldehyde.
Funding SchemeCSC - Cost-sharing contracts