FORMATION OF ISOCYANATES ON NOBLE METALS AND SUPPORTED NOBLE METAL CATALYSTS.

Article abstract of DOI:10.1002/bbpc.198800198

The formation of support-NCO and noble metal-NCO groups on oxide supported noble metal catalysts and high area evaporated metal films during the NO/CO reaction was studied by FTIR spectroscopy. With SiO//2 and Al//2O//3 as supports the results reported in the literature were essentially reproduced. With TiO//2 and ZrO//2 absorption bands in the region between 2000 and 2100 cm** minus **1 were detected, which had not been described before. On evaporated metals NCO-groups could be detected in situ. They are located at 2185 cm** minus **1 for Pd and at 2170 cm** minus **1 for Pt. Based on kinetic measurements the spillover of NCO-groups from the noble metal to the support is proposed as a mechanism for support-NCO formation.