Hydrometallurgical method for recovering metal materials from spent lead-acid storage batteries
AssigneeHydrometal S.p.A.
InventorUmberto Ducati
Life of this patent
Estimating the term…
Abstract
In the method the ground scraps are screened to separate the pole active material, i.e. Pb and PbO.sub.2, as fines. This active material is then reacted in the presence of a strong alkaline solution to yield a minium precipitate. Minium may be subsequently treated with an appropriate acid, such as fluoboric acid, freed of antimony by precipitating the latter with metal lead, and then subjected to electrolysis to recover lead.
Claims14
A hydrometallurgical method for recovering metalliferous materials from spent lead-acid storage batteries, characterized in that it comprises the steps of separating from storage battery scraps the pole active material including mainly lead and lead dioxide in a finely divided form, mixing said active material with a strong alkaline solution selected from solutions of sodium hydroxide and potassium hydroxide in concentrations ranging from 50 to 300 g/l, the ratio of said active material to said alkaline solution being in the 1:1 to 1:100 range, heating said mixture at a temperature in the 100.degree.-120.degree. C. range, so as to react said lead with said lead dioxide to obtain minium (Pb.sub.3 O.sub.4) and separating from said reaction mixture the minium as a product precipitate.
A hydrometallurgical method for recovering metalliferous materials from spent lead-acid storage batteries, characterized in that it comprises the steps of separating from storage battery scraps the pole active material mainly containing lead and lead dioxide in a finely divided form, mixing said active material with a strong alkaline solution selected from solutions of sodium hydroxide and potassium hydroxide in concentrations ranging from 50 to 300 g/l, the ratio of said active material to said alkaline solution being in the 1:1 to 1:100 range, heating said mixture at a temperature in the 100.degree.-120.degree. C. range, so as to react the lead with the lead dioxide to obtain minimum (Pb.sub.3 O.sub.4) separating from the resulting reaction mixture the minium as a product precipitate, subjecting the separated minium to attack by an acid selected from fluoboric acid, fluosilicic acid and sulphamic acid, separating the resulting solution from the solid residue, and subjecting said solution to electrolysis to obtain lead as final product.
Dependencies are inferred from the claim text.