Process and apparatus for vacuum distillation of high-purity magnesium

Abstract A starting material 2 in the form of a magnesium-containing metal melt is present together with the upper region 32 of a condensation vessel 3 in the upper region 11 of a retort 1 heated by the external heating element 5, wherein the steam produced according to the arrows 91, according to arrow 92, enters the upper region 32 of the condensation vessel 3 through the opening 31 below the cover 4 which provides protection from unwanted ingress of contaminated magnesium melt, wherein said steam condenses in the lower region 12 of the retort which is heated by a second heating element 51, below the line 8 corresponding to the melting point isotherm of magnesium, to give the high-purity magnesium melt 21 in the lower region 33 of the condensation vessel 3. By opening a barrier unit 6, the interior of the retort 1 can be connected temporarily to the supply chamber 13, and also via a line 73 and a valve 72 to a vacuum pump 73, via a further line 74 to a pressure measuring instrument 75, and via a third line 76, via a valve 77 and a pressure and/or flow regulator 77 to an inert gas source 79. 13.027P-WO 78 (63 13 -- -71 76' 93 6F--. 1, 83 U-81 xig x