Infrared spectrophotometry study of hydrogen interaction with carbonates adsorbed on ThO2

Observations from this study lead to the following mechanism for the CO/sub 2/ methanation on ThO/sub 2/: CO/sub 2/ (adsorbed as a carbonate on ThO/sub 2/) is first reduced to CO by hydrogen, CO being manifested on the surface as a formate; hydrogenation of CO in a later stage than leads exclusively to methane.