Process for the removal of sulfur from battery wrecker material using ammonium carbonate solution

• US 3,883,348 A
• Filed: 09/06/1973
• Issued: 05/13/1975
• Est. Priority Date: 09/06/1973
• Status: Expired due to Term

• Current Assignee: Floyd A. Acoveno, Thomas W. Freudiger
• Original Assignee: Floyd A. Acoveno, Thomas W. Freudiger
• Inventors: Acoveno, Floyd A., Freudiger, Thomas W.
• Primary Examiner(s): Carter, Herbert T.
• Application Number:
  US05/394,837
• Time in Patent Office: 614 Days
• Field of Search: 75/103,120 423/89,92,98,434
• US Class Current: 75/432
• CPC Class Codes: C01G 21/06 Lead monoxide [PbO]
• CPC Class Codes: C01G 21/14 Carbonates
• CPC Class Codes: C05C 3/00 Fertilisers containing other salts of ammonia or ammonia itself, e.g. gas liquor
• CPC Class Codes: C22B 13/045 Recovery from waste materials
• CPC Class Codes: Y02P 10/20 Recycling

Abstract

A process for the conversion of waste battery scrap materials containing lead sulfate comprising an initial leaching operation to convert such lead sulfate to lead carbonate while at the same time converting the aqueous ammonium carbon solution to ammonium sulfate. Such is followed by filtration to thus separate soluble ammonium sulfate from the insoluble lead carbonate. The ammonium sulfate is then suitably crystallized resulting in a commercial product, namely, a useful fertilizer compound. The lead carbonate referred to in the foregoing is decomposed by application of heat to produce lead oxide and carbon dioxide, the latter then being reacted with aqueous ammonia to produce more ammonium carbonate solution for another beginning leach cycle. The advantages of the system reside in the reduction of emission of noxious sulfur oxides (SOx) in an amount from at least about 80 to 90 percent while at the same time producing a useful commercial product, ammonium sulfate.

Claims

1. A PROCESS FOR THE RECOVERY OF MORE VALUABLE PRODUCTS FROM LEAD SULFATE BEARING MATERIAL, WHICH COMPRISES LEACHING SAID MATERIAL WITH AMMONIUM CARBONATE SOLUTION TO FORM LEAD CARBONATE AND AMMONIUM SULFATE, SEPARATING THE EFFLUENT OF THE LEACHING STEP INTO A SOLID LEAD CARBONATE PRODUCT AND A LIQUID PRODUCT COMPRISING A SOLUTION OF AMMONIUM SULFATE AND CARBON DIOXIDE, RECOVERING CARBON DIOXIDE FROM AT LEAST ONE OF SAID PRODUCTS AND REACTING THE SAME WITH AMMONIA TO FORM AMMONIUM CARBONATE, AND SUPPLYING THE LATTER IN AQUEOUS SOLUTION TO THE AFORESAID LEACHING STEP.

2. The process of claim 1 further characterized in that said carbon dioxide is formed by thermal decomposition of said lead carbonate product.

3. The process of claim 1 further characterized in that said carbon dioxide is obtained by vaporization from said liquid product.

4. The process of claim 1 further characterized in that at least a portion of said ammonia is derived from said ammonium sulfate solution.

5. A process for the recovery of more valuable products from lead sulfate bearing material, which comprises leaching said material with ammonium carbonate solution to form lead carbonate and ammonium sulfate, separating the lead carbonate from the ammonium sulfate and recovering the latter, thermally decomposing the lead carbonate to form lead oxide and carbon dioxide, reacting the carbon dioxide with ammonia to form ammonium carbonate, and supplying the latter in aqueous solution to the aforesaid leaching step.

6. The process of claim 5 further characterized in that said lead oxide is reduced to metallic lead.

7. A process for the recovery of more valuable products from lead sulfate bearing material, which comprises leaching said material with ammonium carbonate solution to form lead carbonate and ammonium sulfate, separating the effluent of the leaching step into solid lead carbonate and a solution of ammonium sulfate, ammonia and carbon dioxide, separating a gas containing ammonia and carbon dioxide from the last-named solution and recovering the ammonium sulfate content of this solution, thermally decomposing said solid lead carbonate into lead oxide and carbon dioxide, commingling the latter with said gas and reacting the carbon dioxide and ammonia content of the resultant mixture to form ammonium carbonate, and supplying the latter in aqueous solution to the aforesaid leaching step.

8. The pRocess of claim 7 further characterized in that said lead oxide is reduced to metallic lead.

9. A process for the recovery of more valuable products from lead sulfate bearing material, which comprises leaching said material with ammonium carbonate solution to form lead carbonate and ammonium sulfate, separating the effluent of the leaching step into solid lead carbonate and a solution of ammonium sulfate, ammonia and carbon dioxide, vaporizing from the last-named solution, by heat exchange thereof with CO2-containing combustion products, a gas containing ammonia and carbon dioxide, separating said gas from the ammonium sulfate and commingling the same with the combustion products issuing from said heat exchange, reacting the ammonia and carbon dioxide content of the resultant gas mixture to form ammonium carbonate, and supplying the latter in aqueous solution to the aforesaid leaching step.

10. The process of claim 8 further characterized in that said lead carbonate is reduced to metallic lead.