It would be almost nothing to say that lithium is produced electrolytically. The electrolytic step is the last stage of the production of this trace element. Even within spodumene amblygonite, the minerals which biggest abundance of lithium, the concentration of the lithium hardly exceeds 7%. At the present time lithium is extracted by decompounding minerals by sulfuric acid (the acid method), sintering with CaO or CaCO3 (the alkalic method), treating with K2SO4 (the salt method) with further water leaching. All methods bring to conversion to the poorly soluble lithium carbonate Li2CO3 which with HCl then provides lithium chloride, LiCl. After that a mixture of lithium chloride (55%) and potassium chloride (45%) melts at about 430°C and so much less energy and so expense is required for the electrolysis. From then on the isolated Lithium is purified by the vacuum distillation method.
Sometimes the reduction reactions with other elements are applied in getting stable lithium oxides: 2Li2O + Si = SiO2 + 4Li.\n |