Characteristics of drying and active component distribution in alumina monoliths using 1H-NMR imaging

During drying of the impregnated washcoated monolith the certain part of the introduced active component precursor (H2PtCl6 or H2PdCl4) is transported from the substrate macropores to the mesoporous washcoated layer which leads to enrichment of the washcoat of the final catalyst by active component. The non-destructive character of 1H-NMR microimaging demonstrated its capability to visualize the water content maps in monoliths in the presence of Pt and Pd.