Abstract: A method of refining crude cadmium by vacuum distillation in which crude cadmium is passed into a reflux condenser in which higher boiling point impurities are condensed together with a portion of pure cadmium vapor, this condensate flowing in counterflow with the crude cadmium vapor. The remaining portion of the pure cadmium vapor is subsequently condensed. The apparatus comprises an inverted U-shaped vacuum chamber having an evaporator and a reflux condenser in one leg and a further condenser in the other leg. A feed pipe for liquid crude cadmium enters the one leg adjacent the evaporator and a residue outlet pipe leaves the one leg, the feed pipe and the residue pipe being arranged so that no back-flow takes place from the residue pipe to the feed pipe. An outlet pipe for the refined cadmium issues from the other leg of the vacuum chamber.

Abstract: A method of refining crude cadmium by vacuum distillation in which crude cadmium is passed into a reflux condenser in which higher boiling point impurities are condensed together with a portion of pure cadmium vapor, this condensate flowing in counterflow with the crude cadmium vapor. The remaining portion of the pure cadmium vapor is subsequently condensed. The apparatus comprises an inverted U-shaped vacuum chamber having an evaporator and a reflux condenser in one leg and a further condenser in the other leg. A feed pipe for liquid crude cadmium enters the one leg adjacent the evaporator and a residue outlet pipe leaves the one leg, the feed pipe and the residue pipe being arranged so that no back-flow takes place from the residue pipe to the feed pipe. An outlet pipe for the refined cadmium issues from the other leg of the vacuum chamber.