An H-1 NMR microimaging visualization of hexachloroplatinate dianion redistribution within a porous gamma-Al2O3 pellet in the course of supported catalyst preparation

The application of the H-1 NMR microimaging technique to the indirect mappi ng of the spatial distribution of hexachloroplatinate dianion within porous alumina pellets is reported. It is demonstrated that the nuclear spin-latt ice relaxation times of liquids filling the pores of the pellet increase in the presence of the adsorbed hexachloroplatinate dianion, The microimaging results for the supported catalysts with two types of platinum distributio n (egg-shell and egg-white) are shown to be consistent with the results obt ained by the staining method and electron probe microanalysis. Finally, the microimaging technique is employed for a nondestructive visualization of t he dynamics of the active component redistribution in the course of the sup ported catalyst preparation by competitive adsorption.