Case Study

Abstract

The effect of zirconium on the textural and catalytic properties of magnetite for the water gas shift reaction (WGSR) at high temperatures was studied in this chapter. The reaction is an important step in the industrial production of pure hydrogen. Samples with different amounts of zirconium (Zr/Fe (molar)= 0.1; 0.2;0.3; 0.4 and 0.5) were prepared from the decomposition of iron(III)hydroxoacetate doped with zirconium. It was found that zirconium increased the specific surface area of magnetite acting as spacer on the surface where it keeps the particles apart. Except for the zirconium-poorest solid, tetragonal zirconia was detected besides magnetite for all solids. Zirconium increased the intrinsic activity of the catalysts, stabilized the specific surface areas during reaction, and made the magnetite reduction to metallic iron more difficult. The zirconium-poorest is more active than magnetite and more resistant against deactivation by sintering and overreduction being attractive for WGSR.