Washcoating of Pt-ZSM5 onto aluminium foams

The anodisation conditions of aluminium foam monoliths are studied in order to produce alumina with controlled properties. When anodisation conditions are extreme, an important cracking of the surface appears with width and depth cracks that depend on the anodisation parameters, i.e., electrolyte temperature, anodisation time and applied current density. Different surface treatments for aluminium foams (rough anodisation, smooth anodisation, and no anodisation) were used to observe the mechanical stability of Pt/ZSM5 coatings. Roughness of the surface improved adhesion of Pt/ZSM5 coatings because the size of the cracks was high enough to occlude the zeolite particles promoting a mechanical anchorage of the coating. The washcoated aluminium foam monoliths were tested in total oxidation of toluene showing very high activity.