A process for bulk hydrogenation of an olefin-containing feedstock containing a plurality of different unsaturated olefinic hydrocarbon compounds, for example a feedstock containing from 60 to 100 mass % unsaturated olefinic hydrocarbon compounds, by subjecting the olefinic feedstock to bulk hydrogenation in a catalytic distillation zone containing a hydrogenation catalyst, and in the presence of hydrogen, under conditions favoring bulk hydrogenation to hydrogenate unsaturated olefinic hydrocarbon compounds present in the feedstock into their corresponding saturated compounds, and withdrawing the saturated compounds from the catalytic distillation zone.