Hydroxyapatite as a novel support for gold and ruthenium catalysts - Behaviour in the water gas shift reaction

Novel catalysts comprising gold or ruthenium supported on hydroxyapatite are prepared by a deposition-precipitation method and examined for their behaviour in the water gas shift reaction at various reaction temperatures and at atmospheric pressure. The physicochemical properties of the catalysts were characterized using BET-surface area (BET-SA), XRD, TPR, TPD of NH3 and CO2. High WGS activities were observed over Au/HAP compared with Ru/HAP catalyst. The Ru/HAP catalyst showed methanation activity at temperatures above 300 degreesC, caused by a tendency for the dissociative chemisorption of CO to occur, though this process can be suppressed to some extent by an increase in the partial pressure of water under reaction conditions. (C) 2002 Elsevier Science B.V. All rights reserved.