Concentration of metal impurities from sodium aluminate solutions by the method of partial precipitation

The possibility for concentration of metal impurities in form of dispersion phase through the method of partial precipitation from sodium aluminate solutions is evaluated. Comparison of this method with the filtration and centrifugal separation methods showed that the basic part of metal ion impurities (excluding alkali ones), contaminating the sodium aluminate solution, is concentrated in the dispersed phase. It is established that about 70-95 % of Cd(2), Cu(2), Zn(2), Ni(2), Fe(2) and Mg(2) impurities may be removed from the sodium aluminate solution by partial precipitation of aluminate solution by partial precipitation of aluminium hydroxide of hydrochloric acid (author)