Tuning the morphology of monolith coatings

Well-defined α-Al2O3-coated monoliths with different channel geometries to be used in the preparation of structured catalysts or sorbents have been prepared by dipping cordierite monoliths in α-Al2O3/water suspensions. Tuning the morphology of α-Al2O3-coated monoliths can be carried out fixing different factors, like pH, α-Al2O3 concentration in the suspension and using dry or pre-wetted monoliths. Two coating geometries, the extremes for square channels, round and quasi-square ones, have been obtained. So, an optimal coating morphology can be chosen depending on the application. Finally, γ-Al2O3 has been used as example of final catalyst support coating with a uniform thickness over the whole channel perimeter.