Binary and ternary amorphous palladium alloys: Characterization, activity and selectivity in hydrogenation of dienes

Pd25Zr75, Pd22Cu10Zr68, and Pd72Cu10Si18 alloy ribbons prepared by the rapid quenching technique, and Pd25Zr75, Pd25Cu10Zr65, Pd80Si20, and Pd72Cu10Si18 alloy powders made by mechanical alloying proved to be amorphous by X-ray diffraction and differential scanning calorimetry. The powder samples after HF treatment have been found to exhibit high selectivity in the semihydrogenation of 1,3-cyclooctadiene: the pronounced drop in the hydrogen uptake after the complete consumption of the diene allows the selective synthesis of the corresponding monoene.