Pt-Cu Bimetallics in H-Y zeolite: microcalorimetric study of the effect of copper on the catalyst acidity

The change in activity and selectivity towards octane isomerization of Pt USY and Pt REY catalysts upon modification with copper is related to the change in the acidity within each type of catalysts. The acidity increase was ascribed to partial removal of Na+ in the case of REY and to stronger electrostatic fields due to the presence of Cu+ ions. Both conversion and selectivity towards C-8 isomers increase with increased acidity.