NOVELTY - Methanation reaction process comprises: preparing nickel-chromium catalyst; providing single reactor vessel; continuously introducing carbon dioxide and hydrogen gas into single reactor vessel over fixed bed comprising the nickel-chromium catalyst; allowing carbon dioxide and hydrogen gas to react in single reactor vessel at a conversion rate in the presence of the catalyst at a reaction temperature; and maintaining the reaction temperature in the single reactor vessel at 205-220 degrees C by controlling a flow rate of one of the carbon dioxide and the hydrogen gas fed to the single reactor vessel.    USE - The process is useful for converting carbon dioxide to methane (claimed).    ADVANTAGE - The process: utilizes an enhanced metal catalyst, thus leading to energy savings by lowering the operating temperature of carbon dioxide methanation, and reducing operating costs and/or lower equipment capital costs; and provides 90-100%, preferably 100% conversion of carbon dioxide to methane with little coke formation.    DETAILED DESCRIPTION - Methanation reaction process comprises: preparing a nickel-chromium catalyst, by combining a nickel(II) salt and a chromium(III) salt with a nucleation promoter and ammonium hydroxide to form a gel comprising a solid and a liquid, allowing the gel to digest to form a mother liquor and an isolatable solid, isolating the solid from the mother liquor, washing the solid, drying the solid, thermally treating the solid to form the nickel-chromium catalyst with a nickel/chromium ratio of 98:2-50:50; providing a single reactor vessel; continuously introducing carbon dioxide and hydrogen gas into the single reactor vessel over a fixed bed comprising the nickel-chromium catalyst; allowing the carbon dioxide and hydrogen gas to react in the single reactor vessel at a conversion rate in the presence of the nickel-chromium catalyst at a reaction temperature; and maintaining the reaction temperature in the single reactor vessel at 205-220 degrees C by controlling a flow rate of one of the carbon dioxide and the hydrogen gas fed to the single reactor vessel, where the conversion rate to methane is 25-100%.