Back to results
US 8,323,595 B1Granted
Recovery of high purity lead oxide from lead acid battery paste
AssigneeToxco, Inc.
InventorsW. Novis Smith, Steven A. Kinsbursky
Life of this patent
Estimating the term…
Abstract
There is provided a process for recovering high purity litharge PbO from spent lead acid battery paste at low temperatures and the further preparation of highly pure lead oxides and Pb(OH)2.
Claims12
In a low temperature process for recovering high purity litharge PbO from lead acid battery paste, the improvement which comprises the steps of;
- A) treating spent battery paste containing Pb3O4, PbSO4 and Pb(SO4)4 with an alkali chloride and sulfuric acid;
- B) treating the product from step A) with soda ash or alkali hydroxide solution to a pH of about 12 to form PbO or PbCO3;
- C) treating the PbO or PbCO3 from step B) with a carboxylic acid having 1-3 carbon atoms to form a solution of lead carboxylate;
- and then
- D) treating the solution of lead carboxylate with an alkali hydroxide to obtain highly pure litharge PbO or Pb(OH)2.
2 more elements
A process for recovering highly pure litharge PbO from spent lead acid battery paste which comprises the steps of;
- 1) treating an aqueous mixture of spent lead acid battery paste with dilute sulfuric acid and then with sodium chloride to reduce any Pb3O4 present to PbO;
- 2) filtering the product of step 1) and washing the filter cake with dilute sodium hydroxide until the pH of the filtrate formed was about 12;
- 3) washing the filter cake of step 2) until a pH of about 8 is obtained and then treating an aqueous mixture of the filter cake with acetic acid and maintaining a temperature at 60-80° C. to form a solution of lead acetate;
- 4) adding the filtrate containing lead acetate from step 3) to a sodium hydroxide solution at elevated temperatures to obtain pure litharge PbO, and then
- 5) recovering the litharge PbO.
2 more elements
Dependencies are inferred from the claim text.