US8877674-B2  Yaccato et al., "Competitive CO and CO2 methanation over supported noble metal catalysts in high throughput scanning mass spectrometer," Applied Catalysis A: General 296 (2005) 30-48.;  Kramer et al., "Highly selective CO methanation catalysts for the purification of hydrogen rich gas mixtures" J. Catal. 251 (2007) 410-422.;  Men et al., "Selective methanation of carbon oxides in a microchannel reactor_primary screening and impact of gas additives," Catalysis Today 125 (2007) 81-87.;  Liu et al., "Selective catalytic methanation of CO in hydrogen rich gases over Ni/ZrO2 catalyst," J. Natural Gas Chem. 17 (2008) 268-272.;  Choudhury et al., "Preferential methanation of CO in a syngas involving CO2 at lower temperature range," Applied Catalysis A: General 314 (2006) 47-53.;  Rehmat et al., "Selective Methanation of Carbon Monoxide," Ind. Eng. Chem. Prod. Res. Develop. (1970) 512-515.;  Cheekatamarla et al., "Selective low temperature removal of carbon monoxide from hydrogen-rich fuels over Cu-Ce-Al catalysts," J. Power Sources 147 (2005) 178-183.;  Andersson, "Toward computational screening in heterogeneous catalysis: Pareto-optimal methanation catalysts," J. Catal 239 (2006) 501-506.;  Habazaki et al., "CO-methanation of carbon monoxide and carbon dioxide on supported nickel and cobalt catalysts prepared from amorphous alloys," Appl. Catalysis A: General 172 (1998) 131-140.;  Panagiotopoulou et al., "Selective methanation of CO over supported noble metal catalysts: Effects of the nature of the metallic phase on catalytic performance," Appl. Catalysts A: General 344 (2008) 45-54.;  Takenaka et al., "Complete removal of carbon monoxide in hydrogen-rich gas stream through methanation over supported metal catalysts," Intl. J. Hydrogen Energy 29 (2004) 1065-1073.;  Dagle et al., "Selective CO methanation catalysts for fuel processing applications," Applied Catalysis A: General (2007) 213-217.;  Bianchi et al., "CO Hydrogenation over Co/SiO2 Catalysts Prepared by Different Ways," Symposium on Fischer-Tropsch Chemistry, 219th Meeting ACS, San Francisco, CA Mar. 2000.;  Boerrigter and Rausch "Review of applications of gases from biomass gasification," Jun. 2006, pp. 1-31.