| 摘要 |
Calcium carbide is dissolved in a bath of anhydrous calcium chloride, and the obtained solution is contacted with a dispersion of a molten metal phase, e.g. lead, having a strong affinity for calcium, so that a alloy of the molten metal phase and calcium is formed. The alloy is then decomposed by physical or electrochemical refining to produce calcium and to regenerate the molten metal phase. The metal phase can comprise: (a) lead in order to form an alloy of lead and calcium containing 2-5 wt. % calcium; (b) tin in order to form an alloy of tin and lead containing 3-5 wt. % calcium; or (c) an alloy comprising chemical compositions of lead, tin, copper, aluminum and nickel. Preferably, calcium is separated from the formed alloy by vacuum electro-refining in a bath of calcium chloride, by electro-refining under argon pressure in a bath consisting of a mixture of strontium chloride, barium chloride and calcium chloride, or by vacuum distillation. |
