Improving the Sulphur Tolerance of Nickel Catalysts for Running Solid Oxide Fuel Cells on Waste Biogas

To explore the possibility of running Solid Oxide Fuel Cells (SOFC) on biogas, reactions of 2/1 CH4/CO2 gas mixtures over Ni/YSZ (yttria-stabilised zirconia) SOFC anode materials have been investigated using on-line quadrupole mass spectrometry in the temperature range 750-1000°C. Carbon deposition has been analysed by post-reaction temperature programmed oxidation (TPO). Hydrogen sulphide (H2S) added to the reactant stream established the effect of sulphur containing gases on the reforming characteristics, carbon deposition and durability of nickel-based anodes. In addition to investigating the behaviour of a conventional Ni/YSZ anode, the performance of gold-, hafnia- and ceria-doped Ni/YSZ anodes were also studied in terms of their influence on the reforming activity, carbon deposition and sulphur tolerance.