• Nahil, Mohamad A.
• Jaffar, Mohammad M.
• Williams, Paul

Abstract

<jats:sec><jats:label /><jats:p>The production of methane by carbon dioxide hydrogenation through optimization of the operating parameters to enhance methane yield and carbon dioxide conversion in a two‐stage fixed bed reactor is investigated. The influence of temperature, gas hourly space velocity (GHSV), and H<jats:sub>2</jats:sub>:CO<jats:sub>2</jats:sub> ratio on the production of methane is studied. In addition, different methanation catalysts in terms of metal promoters and support materials are investigated to maximize methane production. The results show that the maximum methane yield and maximum carbon dioxide conversion are obtained at a catalyst temperature of 360 °C with a H<jats:sub>2</jats:sub>:CO<jats:sub>2</jats:sub> ratio of 4:1 and total GHSV of 6000 mL h<jats:sup>−1</jats:sup> g<jats:sup>−1</jats:sup><jats:sub>catalyst</jats:sub> and reactant GHSV of 3000 mL h<jats:sup>−1</jats:sup> g<jats:sup>−1</jats:sup><jats:sub>catalyst</jats:sub>. The optimum metal‐alumina catalyst investigated for CO<jats:sub>2</jats:sub> conversion and methane yield is the 10 wt%‐Ni‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> catalyst. However, reduction in the methane yield is observed with the addition of Fe and Co promoters because of catalyst sintering and nonuniform dispersion of metals on the support. Among the different catalyst support materials studied, i.e., Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, SiO<jats:sub>2</jats:sub> and MCM‐41, the highest catalytic activity is shown by the Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> catalyst with 83 mol% CO<jats:sub>2</jats:sub> conversion, producing 81 mol% CH4 with 98% CH<jats:sub>4</jats:sub> selectivity.</jats:p></jats:sec>

Topics

• impedance spectroscopy
• dispersion
• Carbon
• size-exclusion chromatography
• sintering