Palladium/perovskite/zirconia catalytic premixed fiber burners for efficient and clean natural gas combustion

The present work was aimed at developing and testing – under realistic operating conditions on a specifically assembled pilot plant – a novel generation of catalytic premixed fiber burners for low-environmental-impact natural gas combustion. The adoption of a palladium-LaMnO3-zirconia catalyst developed on purpose, where zirconia acts as a structural promoter and the noble metal/perovskite synergism is effectively exploited, led to enhanced performances with respect to non-catalyzed burners. In particular, lower CO and NOx emissions were recorded over a wide field of operating conditions (basically excess of air with respect to the stoichiometric condition and nominal heat power). Also, the effect of ageing and poisoning induced by sulfur compounds added as odorants in the natural gas network was studied, with promising indications as regards the burners durability: the overall performance, in terms of pollutant emissions, appeared to have slightly improved after prolonged exposure to SO2 and high temperatures.