The activity and selectivity of Ru catalysts to CH4 is however largely dependent on the dispersion of metallic phase, on the type of the support and addition of modifiers/promoters that can chemically interact with the metal [22]. Ru catalysts have been supported on a number of oxide materials such as Al2O3, TiO2, SiO2, MgO, MgAl2O4, CeO2 [30]. The nature of the support affects the mechanism for hydrogenation reactions of CO/CO2, since the metal support interaction modifies the adsorption of the intermediates as well as desorption of the products. In addition, catalytic performance of dispersed metal catalysts for methanation reactions is often affected by metal loading and crystallite size in a manner which depends on operating conditions used and metal–support combination employed [19].