A nickel-activated alumina candle filter shows potential for the combined removal of particles, tars and ammonia from biomass gasification gas at high temperature. To deposit the nickel catalyst in the filter, only methods applicable to a preformed support can be considered. In this paper, we investigated the incorporation of a nickel precursor into small-scale alpha-Al2O3 filter substrates with a mean pore radius of 26 mu m. Two preparation routes were used and compared: deposition-precipitation with urea:and nickel nitrate and conventional impregnation with nickel nitrate. The substrates were characterised by X-ray mapping (SEM/EDX), mercury porosimetry and krypton adsorption. Preliminary experiments with the urea method have shown that an appropriate selection of the reaction time and the urea/nickel molar ratio is necessary to obtain a high controlled fixation of precursor during the slow decomposition of urea. The urea method gave a fairly uniform distribution of the nickel precursor throughout the support bodies. On the contrary, with the conventional impregnation method, most of the precursor was found in the outer pores of the substrate. Both methods can be repeated to increase the catalyst loading. Performing twofold deposition cycles, it was found that the urea method was more reliable and still gave a good distribution of the precursor. (C) 2000 Elsevier Science B.V. All rights reserved.