Catalytic combustion of sulphur-bearing gasified biomass

Precious metal based catalyst Pd/LaAl 11O 19 and Pt/LaAl 11O 19 were prepared and characterized by means of XRD and BET. Then washcoated on cordierite monoliths and tested in a bench scale reactor with a synthetic low-heating value fuel that resembles the gas from gasification of biomass. besides 0.005% hydrogen sulphide were added to the fuel to investigate the influence of sulphur on the catalytic combustion. Combined the characterization results of XPS, SEM and FTIR after the activity tests, a preliminary analysis of the mechanism for the sulfur poisoning of the catalysts were deduced. The results show excellent catalytic activity for the catalysts which significantly reducing the ignition temperature of combustible ingredients, the low temperature activity for Pd was superior to Pt. Besides all samples were deactivated to some extent by addition of sulphur, although poisoning effect varied depending on the active phase. The poisoning processes mainly through the formation of sulfate which deposition on the surface composition, then covered the active site resulting a decrease in catalytic activity.