Reusability of the Cu/Ni-based colloidal catalysts stabilized by carboxylates of alkali-earth metals for the one-step amination of dodecyl alcohol and dimethylamine

The Cu/Ni-based colloidal catalyst, stabilized by barium stearate (Cu:Ni:Ba mole ratio 5:1:1; particle size 1-5 nm), for the one-step amination of dodecyl alcohol and dimethylamine to N,N-dimethyldodecylamine at Cu concentration ranges of 300-1000 ppm at 200-210 °C, could be recovered by distillation and could be reused several times without a decrease in the activity. The activity of the concentrated activated colloidal catalysts for the amination reaction was not decreased for a month. These observations demonstrated that the reusability and stability of the Cu/Ni-based colloidal catalysts were enough for the commercial operation, which opposed to the claim that a colloidal catalyst cannot be recovered and reused. The Cu/Ni/Ba colloidal catalyst is the first example of a metallic colloid applied for the amination reaction.