Development of Desulfurization Sorbents for Ultra Cleanup of Hot Fuel Gas

抄録

Metal oxide sorbents with high surface area for ultra hot gas cleanup were prepared by a matrix assisted method. A granule type of activated carbon was used as a matrix in order to increase the surface area of the metal oxide. Zn was loaded on the surface of activated carbon by an impregnation method. Metal oxide maintained in the form of matrix structure was observed by SEM. Wurtzite structure of ZnO was also confirmed in XRD measurement of the prepared granular particle. Particle size of metal oxide was distributed in the range of 5-50 nm from TEM image. Surface area of zinc oxide calcined at 500°C was around 56m²/g. The values of the particle size and surface area were directly related to the temperature of calcination. The sulfidation rate curves for the high surface area zinc oxides measured by Cahn balance at several different temperatures for calcinations. It was obtained that a catalyst with a large surface area showed a high activity in the reaction. Not only sulfur content in a simulated coal gas was completely removed by the high surface area ZnO but also COS formed by secondary reaction was not detected in the sulfidation tests performed in a fixed-bed reactor system. It was believed that the high surface area ZnO prepared in this study is a suitable sorbent for the ultra hot gas cleaning from the experimental result.