Reconstruction of the surface layer of platinum group metals in the thermal treatment in various gases and propane hydrogenolysis

The enrichment with ruthenium of the surface layer of a Pd-Ru alloy tube during the propane hydrogenolysis was observed. Metal particles immobilized within carbonaceous deposits and filamentous crystals of the metals with a carbon cover are formed on the Rh and Ir wires. Thermal treatment in gases free of carbon compounds does not cause such a deep reconstruction. The deep reconstruction occuring during the propane hydrogenolysis is the stronger, the greater the amount of carbon this metal dissolves.