Adsorption of Reactants on Supported Metals

The adsorption of H2 on metals needs only a brief treatment. Much information is already available on this topic (see, e.g., refs. 60-62) and it seems that the metals (compare, e.g., Ni, Co, with Rh, Ir, Pd, or Pt) do not differ as much in adsorption of H2 as they do with regard to the FTS or synthesis of oxygenates. Adsorption of H2 on transition metals is dissociative, non-activated, mobile above about — 100°C, forming islands on flat metal surfaces (when adsorbed alone) and preferentially occupying surface holes. Examples of relevant experimental evidence can be found in recent papers. Ions of transition metals can bind H atoms and are therefore active centres for hydrogenations or deuterium-exchange reactions of hydrocarbons the 

Somorjai, Chemistry in Two Dimensions Surfaces , Cornell University Press, Ithaca, 1981. 

Hirschwald in Current Topics in Materials Science , ed. E. Kaldis, North-Holland, Amsterdam, 1981, Vol. 7, p. 143. 

in Catalysis , Proc. Vth Int. Congr. Catal., Miami Beach, 1972, ed. J. W. Hightower, North-Holland, Amsterdam, 1973, Vol. 1, p. A-1. 

Interaction of surfaces with oxygenates forms a more extended subject than adsorption of H2 and could be itself a subject of a review. However, let us briefly mention some features of methanol adsorption. On metals, the adsorption begins from the gaseous phase by splitting H from the OH group, as can be inferred from the methanol/D2 exchange reaction and the i.r. spectra. At slightly elevated temperatures, the M-O-CH3 species 

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