The activation after the thermal treatment is
observed for Pd/CoCe/Al2O3, and Pd/Ni/Al2O3
samples.
Remarkable deactivation proceeds when the
samples are modified with Mn - oxides
(Pd/Mn/Al2O3 and Pd/CoMn/Al2O3). The decrease
in the number of active centers might be due to
partial decoration of Pd from manganese oxide.