(617hm) Effect of Poisoning on Low Temperature Methane Dry Reforming Pt-Ni-Mg/Ceria-Zirconia Catalysts

Silica poisoning of low temperature methane reforming catalyst comprised of platinum (0.16wt. %) and/or nickel (1.4 wt. %) and magnesium (1.0 wt. %) immobilized onto a ceria-zirconia support was studied. This was done to determine the effect of siloxane containing landfill gas which ultimately can decompose to silica over the reforming catalyst. The catalyst was poisoned using three different silica amounts corresponding to 1 week, 1 month and 6months concentrations found in landfill gas. XRD patterns demonstrated that silica was present in the catalyst as a depression in the lower 2theta range appeared. Temperature-programmed reduction showed that addition of silica adversely affected the reduction temperature. At the highest amount, the reduction temperature increased from 242°C to 315°C. Dry reforming of the poisoned catalyst also showed a decrease in catalytic activity where the lowest CH₄ and CO₂ conversion (X₁₀) temperatures were achieved at 586.8°C and 563.8°C respectively for the poisoned versus at 454°C and 437°C respectively for the un-poisoned platinum-containing catalyst.