Rubidium is obtained during processing mineral feedstock in production of other valuable components. The obtained concentrates contain also such impurities as caesium and potassium. For this reason the enriched concentrate is then refined from these elements.
Rubidium is usually separated from lepidolite lithium processing. Rubidium is settled from mother solutions, after Li2CO3/LiOH isolation, as potassium, rubidium, or caesium alums Metal Al(SO4)2x12H2O. The mixture is resolved by fractional crystallization. As an alternative source a worked out electrolyte may be applied from which Rubidium may be isolated by sorption on ferrocyanide residues. Rb2CO3 with potassium and caesium impurities is obtained from roasted ferrocyanide. Sorption on granular ferrocyanide pellets in chromatographic columns with NH4Cl water solution as an eluent is more efficient. After pollute vaesium processing Rubidium may be separated from mother waters after Cs3[Sb2Cl9] settled out. Rubidium may be yielded also as a by-product of nepheline alum earth processing. |