Abstract: A process for purification of molten salt electrolytes containing magnesium chloride in which oxygen-containing impurities such as magnesium hydroxychloride are destroyed both electrolytically and chemically. The process comprises passing a direct current through a magnesium chloride-containing molten salt electrolyte, thereby electrolyzing a portion of the oxygen-containing impurities at the anode. In addition, the voltage and current of the direct current are sufficiently high to cause electrolysis of a small proportion of the magnesium chloride present in the electrolyte to thereby produce finely dispersed droplets of elemental magnesium in the electrolyte. The droplets of elemental magnesium react chemically with oxygen-containing impurities present in the electrolyte. The purified electrolyte is transferred to an electrolytic cell for the production of magnesium metal and chlorine gas.

Abstract: A casting furnace for continuous casting of magnesium comprises a furnace body divided into at least two compartments by at least one vertical weir. Inside each compartment, an upper layer of molten magnesium is in contact with a lower layer of a liquid heating medium, preferably a molten salt. The top of the weir is situated below a maximum level of the molten magnesium in the furnace. The weir is free of openings between its top and the magnesium/salt interface. The molten magnesium from primary (electrolytic) production or an alloy preparation furnace is introduced into a feed compartment of the furnace through a discharge pipe having means to direct the magnesium horizontally along the magnesium/salt interface, thereby minimizing intermixing of the magnesium and salt layer.

Abstract: A process for purification of molten salt electrolytes containing magnesium chloride in which oxygen-containing impurities such as magnesium hydroxychloride are destroyed both electrolytically and chemically. The process comprises passing a direct current through a magnesium chloride-containing molten salt electrolyte, thereby electrolyzing a portion of the oxygen-containing impurities at the anode. In addition, the voltage and current of the direct current are sufficiently high to cause electrolysis of a small proportion of the magnesium chloride present in the electrolyte to thereby produce finely dispersed droplets of elemental magnesium in the electrolyte. The droplets of elemental magnesium react chemically with oxygen-containing impurities present in the electrolyte. The purified electrolyte is transferred to an electrolytic cell for the production of magnesium metal and chlorine gas.