Nickel supported on rice husk ash — activity and selectivity in CO 2 methanation

Abstract

In this study, we prepared rice husk ash-supported nickel catalyst by incipient wetness impregnation in methanation of CO 2 from H 2/CO 2 (4/1) mixture. High selectivity (80–90%) for CH 4 formation was found to proceed in the reaction at 623–973 K with the supported nickel. During the investigations of preparation conditions, effects of nickel loading, immersion time, calcination and reaction temperature on catalytic performance were also examined. According to these results, the metal dispersion increases with a decreasing nickel loading. The conversion of CO 2 and the yield of CH 4 depend on calcination conditions. In addition, the nickel catalyst activity is independent of immersion time; the CH 4 yield achieves a maximum value in CO 2 methanation at 773 K. Moreover, rice husk ash is found to be a preferable catalyst support over silica gel by TPD techniques and the reaction test.