Four commercial catalysts for steam reforming of higher hydrocarbons (naphthas) and three for steam reforming of light hydrocarbons are tested for hot gas clean up and upgrading in biomass gasification with air in fluidized bed. The catalysts used originate from four manufacturers:  BASF AG, ICI-Katalco, Haldor Topsoe a/s, and United Catalysts Inc. The work is performed in a small pilot plant (1−2 kg of biomass fed/h) with three reactors in series:  gasifier, guard bed of dolomite, and full flow catalytic bed. Samples of gas are taken before and after the catalytic bed at different times-on-stream. It is shown how the H2, CO, CO2, CH4 and steam contents in the flue gas change because of the catalytic bed approaching contents near to the ones corresponding to the equilibrium state. Variations in the heating value of the gas and gas yield as a result of the catalytic bed are also reported.

Seven different commercial nickel-based catalysts for steam reforming of light hydrocarbons and of heavier hydrocarbons were tested for tar removal in a flue gas from an atmospheric fluidized bed biomass gasifier, using air as the gasifying agent. The catalysts were provided by BASF AG, ICI-Katalco, Haldor Topsoe a/s, and United Catalyst Inc. The facility used is a small pilot plant, and the catalytic reactor operates in full flow with a real gasification gas. A guard bed with a calcined dolomite is used to decrease the tar content at the inlet of the catalytic bed to a level below 2 g/m 3 n . The variables studied include the temperature (730-850 °C) of the catalytic bed, gas residence time, steam content in the flue gas, and composition of the reacting atmosphere. All catalysts for steam reforming of naphthas provide a similar and very high activity. Values of the apparent activation energy and preexponential factor are given and analyzed for the most active catalysts. The catalyst life is also studied. No deactivation is observed with times-onstream of up to 65 h.

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