Methanation

The methanation reactions of COx were first discovered by Sabatier and Senderens in 1920.[1]

COx methanation have many practical application as a means of CO removal from process gases for gas separation purposes and is also being discussed as an alternative to PROX in fuel processors for mobile fuel cell applications[2]

In recent years, due to the rise of the natural gas price, the synthetic natural gas production through methanation would constitute an economical asset to reduce gas import dependeance. Meanwhile, the actively investigated hydrogen production by photocatalytic or electrocatalytic water splitting powered by renewable energies (solar or wind) is regarded as future sources of hydrogen for carbon dioxide hydrogenation.

Chemical reactions

The following reactions describe the methanation of carbon monoxide and carbon dioxide respectively:

CO + 3 H2 CH4 + H2O

CO2 + 4 H2 CH4 + 2 H2O

The methanation reactions are classified as exothermic. Hence, according with Le Chatelier's principle, to promote methane production, methanation reactions should be performed at low temperature and high pressure.

Methanation reaction over different carried metal catalysts including Ni,[3] Ru [4] and Rh[5] has been widely investigated for the production of CH4 from syngas.

References

  1. ↑ E. K. Rideal, «Presidential address. Concepts in catalysis. The contributions of Paul Sabatier and of Max Bodenstein», Journal of the Chemical Society, 1951, p. 1640-1647 ([DOI:%2010.1039/JR9510001640 lire en ligne])
  2. ↑ Yong Men, «Selective methanation of carbon oxides in a microchannel reactor—Primary screening and impact of gas additives», Catalysis Today, 2007, p. 81-87 ([doi:10.1016/j.cattod.2007.02.017 lire en ligne])
  3. ↑ K.O. Xavier, «Doping effects of cerium oxide on Ni/Al2O3 catalysts for methanation», Catalysis Today, 1999, p. 17-21
  4. ↑ Toshimasa Utaka, «CO removal from reformed fuels over Cu and precious metal catalysts», Applied Catalysis A: General, 2003, p. 117-124 ([10.1016/S0926-860X(03)00048-6 lire en ligne])
  5. ↑ Paraskevi Panagiotopoulou, « Selective methanation of CO over supported noble metal catalysts: Effects of the nature of the metallic phase on catalytic performance», Applied Catalysis A: General, 2008, p. 45-54 ([10.1016/j.apcata.2008.03.039 lire en ligne])


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