Positron annihilation spectroscopy for chemical analysis (PASCA) has been applied to differentiate a multicomponent system from the individual constituents. The model catalysts used for this study were a Pt ion exchanged with mordenite and then extruded with Al2O3 and Pt impregnated onto a formed mordenite-Al2O9 extrudate. Differences were observed between the extrudates and mixed blends of the individual components. This result suggests that the extrusion may modify the location or interaction of the Pt and that PASCA has potential for the characterization of multicomponent catalysts.