5A zeolite (LTA 5A) was employed as nickel catalyst support for carbon dioxide hydrogenation at various concentrations of nickel, i.e. i.e. 5, 10, 15 and 20wt%. The catalysts were simply prepared by incipient wetness impregnation and nickel nitrate hexahydrate was employed as precursor. Calcination of catalyst at 650°C is related to thermal decomposition. Prior to carbon dioxide hydrogenation, reduction of catalysts was conducted at 600°C for 2 hours. Carbon dioxide methanation was carried out under atmospheric pressure at different temperatures varied from 200 to 500°C. The carbon dioxide was mixed with hydrogen at stoichiometric ratio of 1:4 and the catalyst composed of 15wt% nickel was the most active catalyst amongst others and gave nearly 80% of CO_2 conversion and selectivity to methane was found at 60% whereas thermodynamic equilibrium gave % conversion nearly to 50% and 100% selective to methane. Increasing nickel more than 15wt% can cause agglomeration of nickel particles and lowering catalytic activity.
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