摘要 |
Process for preparing an alkali metal from a salt of the alkali metal which is soluble in a solvent, including a first electrolysis, a concentration, and a second electrolysis. The first electrolysis produces a product mixture. This product mixture is then concentrated to give a largely solvent-free alkali metal (poly)sulfide melt. A second electrolysis at a temperature above the melting point of the alkali metal is then performed in a second electrolysis cell comprising an anode space and a cathode space, separated by a solid electrolyte which conducts alkali metal cations. The alkali metal (poly)sulfide melt from the concentration step is fed to the anode space. Sulfur is removed from the anode space and liquid alkali metal is removed from the cathode space. |