ADSORPTION MODEL OF METHANOL SYNTHESIS REACTANTS ON CUO-ZNO-AL2O3 CATALYST .2. ADSORPTION ON THE INDIVIDUAL COMPONENTS OF THE CATALYST

Adsorption isotherms and isosteric heats of adsorption of the methanol synthesis reactants have been determined for the components of the reduced catalyst CuO-ZnO-Al2O3. It has been found that the components of the catalyst interact, which leads to changes in concentration of the adsorption centres, binding energy of the adsorbates and adsorption mechanism. Centres involving Cu+ ions in the ZnO matrix, which are electron acceptors, adsorb reversibly CO and CO2, whereas they bind irreversibly water and methanol. The reversible adsorption of water and methanol occurs at the centres consisting of an excess zinc atom and an oxygen vacancy.