The CO Methanation Over The Rh and Ru Promoted NiO-CeO2-ZrO2 Catalysts

Abstract

In this study, Rh and Ru promoted NiO-CeO2-ZrO2 catalysts were prepared with different Rhand Ru loadings (3, 4, 5 (wt.%)) by using two different methods. N2 phsisorption, X-Raydiffraction, scanning electron microscope with energy-dispersive (SEM-EDX) techniques wereused in order to characterize the catalysts. Catalytic activities of the catalysts were tested for COmethanation. The selective CO methanation catalytic activity tests were made over the mostactive catalysts. The effect of the Rh and Ru loading and preparation method on the COmethanation was discussed. The Ru and Rh have different effect on the surface areas of thecatalysts and identifiable peaks for Rh and Ru not observed from the XRD analysis. Because ofthe low ratio of Rh and Ru in catalysts structures, both Ru and Rh containing catalysts gavesimilar CO methanation activity results. The 50% conversion temperatures of the 3% Ru/NiOCeO2-ZrO2catalysts which were prepared by the co-precipitation and surfactant assisted coprecipitationare 191 C and 185 C, respectively. Selective CO methanation was made over the3% Ru/NiO-CeO2-ZrO2 catalysts. Catalysts gave good activity until 300 C. Because of thereversed water gas shift reaction activities of the catalysts were decreased after this temperature.