Process for obtaining pure litharge from lead acid battery paste

1. A process for obtaining high purity litharge (PbO) from spent lead acid battery paste which comprises the steps of:

1) treating lead add battery paste with a reducing agent selected from the group consisting of sodium meta bisulfite and SO 2 in an acid medium to form an aqueous slurry;

2) adding a base selected from the group consisting of an alkali hydroxide and sodium carbonate to the aqueous slurry;

3) filtering the slurry to form a cake and washing the cake;

4) adding the cake to a quantitative amount of acetic acid in water to form a concentrated solution of lead acetate;

5) filtering the solution to remove any insolubles; and

6) adding a base to the solution at an elevated temperature to form litharge, the base being selected from the group consisting of sodium hydroxide and potassium hydroxide.

2. The process of claim 1 wherein the adding the base to the solution is performed at a temperature of about 50° C. to 100° C.

3. The process of claim 1 which comprises treating the lead acid battery paste at a pH of less than 4 with said reducing agent.

4. The process of claim 3 wherein sulfuric acid is used to maintain the pH to less than 4.

5. The process of claim 1 wherein the reducing agent is SO 2 .

6. The process of claim 1 wherein the reducing agent is sodium meta bisulfite.

7. The process of claim 1 wherein the base is sodium carbonate.

8. The process of claim 1 wherein the base is selected from the group consisting of sodium hydroxide and potassium hydroxide.

9. The process of claim 1 wherein the acid medium is formed with an acid selected from the group consisting of acetic acid and sulfuric acid.

10. The process of claim 1 wherein the litharge is further heated in air at 475° C. to form red lead.