Monolayer dispersion close-packed model

According to a simple model based on the assumption that the anions of oxide or salt form a close-packed monolayer on the surface of the support and the cations occupy the interstices left over by anions, one can figure out the close-packed monolayer capacity for oxide or salt on a unit area of the support. We estimate it at 0.10 g/100 m2 or higher for various active components (see later, Table II). The specific surface of the support is about 200 m2/g for y-Al203, 300 m2/g for silica gel, and 1000 m2/g for active carbon. Although each of the catalysts in Fig. 1 contains a considerable amount of active component, its content is still lower than that estimated on the basis of a close-packed monolayer. Therefore, the monolayer dispersion in many of these catalysts does not correspond to the full coverage of the support surface, and more precisely is known as submonolayer dispersion. 

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