The influence of water on the oxygen-silver interaction and on the oxidative dehydrogenation of methanol

Experiments carried out using temperature-programmed desorption and reduction could detect no interaction between water and silver at 200 °C. However, separate experiments on the effect of water on the oxidative dehydrogenation of methanol over a silver catalyst showed that water affected the selectivity of the reaction, reducing the production of CO2. It is suggested that this change in selectivity arises from the adsorption of water on the weakly bound oxygen surface species which are responsible for the non-selective reaction to CO2. The interaction is apparently too weak to give rise to observable species in the t.p.d. and t.p.r. experiments