Process and apparatus for vacuum distillation of high-purity magnesium

Patent metadata

Field	Value
Publication number	US-2017247776-A1
Application number	US-201715595480-A
Country	US
Kind code	A1
Filing date	May 15, 2017
Priority date	Jan 19, 2012
Publication date	Aug 31, 2017
Grant date	—

Abstract

A process for producing high-purity magnesium by means of distillation at reduced pressure, characterized in that, the high-purity magnesium condenses in the liquid state, whereby the starting material in the form of a magnesium-containing melt is present together with the upper region of a condensation vessel in the upper region of a retort, whereby the retort consist of a material that releases no volatile impurities into the magnesium steam, whereby the upper region of the retort is brought to a temperature above the boiling point of magnesium, within the limits of two level lines, and is then held constant, such that steam rises from the boiling magnesium-containing metal melt and fills the interior of the upper region of the retort, whereby the steam infiltrating the upper region of the condensation vessel condenses below the lower level line and collects as high-purity melt in the lower region of the condensation vessel, and whereby in order to prevent contaminated melt that drops from the region above the upper level line from reaching the opening of the condensation vessel, this is protected by a cover, which conveys the impure magnesium back again into the melt.

First claim

What is claimed is:

1 . A process for producing high-purity magnesium by means of distillation at reduced pressure, characterized in that,
the high-purity magnesium condenses in the liquid state, whereby the starting material in the form of a magnesium-containing melt is present together with the upper region of a condensation vessel in the upper region of a retort, whereby the retort consist of a material that releases no volatile impurities into the magnesium steam, whereby the upper region of the retort is brought to a temperature above the boiling point of magnesium, within the limits of two level lines, and is then held constant, such that steam rises from the boiling magnesium-containing metal melt and fills the interior of the upper region of the retort, whereby the steam infiltrating the upper region of the condensation vessel condenses below the lower level line and collects as high-purity melt in the lower region of the condensation vessel, and whereby in order to prevent contaminated melt that drops from the region above the upper level line from reaching the opening of the condensation vessel, this is protected by a cover, which conveys the impure magnesium back again into the melt.

2 . The process according to claim 1 , characterized in that, the retort is heated by a heating system outside the retort.

3 . The process according to claim 1 , characterized in that, a minimum pressure is maintained within the retort, which brings the boiling point of the magnesium above the temperature prevailing in the lower region of the condensation vessel.

4 . The process according to claim 1 , characterized in that, the retort is evacuated via the supply chamber and then brought to the temperatures necessary for the distillation process.

5 . The process according to claim 1 , characterized in that, the pressure in the supply chamber is monitored.

6 . An apparatus for producing high-purity magnesium by means of distillation at reduced pressure, the apparatus comprising:
a retort and a condensation vessel protected by a cover, whereby an upper region of the condensation vessel is in an upper region of the retort, whereby the upper region of the retort is surrounded by a heating element, suitable for heating the upper region of the retort between two different level lines to a temperature above the boiling point of magnesium, and whereby the condensation vessel is arranged in a way, that the lower part of the condensation vessel is located below the lower level line.

7 . The apparatus according to claim 6 , characterized in that, the retort is made of stainless steel.

8 . The apparatus according to claim 6 , characterized in that, the cover comprises graphite.

9 . The apparatus according to claim 6 , characterized in that, a supply chamber is connected to the retort, whereby the supply chamber is connected with means for evacuating the retort.

10 . The apparatus according to claim 9 , whereby the supply chamber is arranged above the retort.

Assignees

• Eth Zuerich

Inventors

• Wegmann Christian
• Loeffler Joerg
• Uggowitzer Peter
• Becker Minh
• Feichtinger Heinrich

Classifications

• F27B5/18 Primary

  Arrangement of controlling, monitoring, alarm or like devices · CPC title

• B01D5/00

  Condensation of vapours; Recovering volatile solvents by condensation (B01D8/00 takes precedence; condensers F28B) · CPC title

• F27B5/14

  Arrangements of heating devices · CPC title

• C22B9/04 Primary

  Refining by applying a vacuum · CPC title

• F27B5/04

  adapted for treating the charge in vacuum or special atmosphere · CPC title