Hydrometallurgical electrowinning of lead from spent lead-acid batteries

Patent metadata

Field	Value
Publication number	US-2017170531-A1
Application number	US-201615145256-A
Country	US
Kind code	A1
Filing date	May 3, 2016
Priority date	Dec 14, 2015
Publication date	Jun 15, 2017
Grant date	—

Abstract

The present disclosure relates generally to recycling lead-acid batteries, and more specifically, relates to purifying and recycling the lead content from lead-acid batteries. A method includes reacting a lead-bearing material with a first carboxylate source to generate a first lead carboxylate. The method includes reacting the first lead carboxylate with a second carboxylate source to generate a second lead carboxylate. The method further includes applying an electrical bias to an aqueous solution of the second lead carboxylate to generate metallic lead.

First claim

1 . A method, comprising:
reacting a lead-bearing material with a first carboxylate source to generate a first lead carboxylate; reacting the first lead carboxylate with a second carboxylate source to generate a second lead carboxylate; and applying an electrical bias to an aqueous solution of the second lead carboxylate to generate metallic lead.

2 . The method of claim 1 , wherein the first carboxylate source comprises an acetate and the second carboxylate source comprises a citrate.

3 . The method of claim 1 , comprising processing spent lead-acid batteries to generate the lead-bearing material, wherein the lead bearing material comprises grids, posts, interconnects, plates, spines, battery paste, lead oxides, or lead sulfates, or combinations thereof, extracted from the processed spent lead-acid batteries.

4 . The method of claim 1 , wherein the first lead carboxylate is generated in a leaching mixture, and wherein the generated first lead carboxylate is dissolved in a liquid component of the leaching mixture.

5 . The method of claim 1 , wherein the second lead carboxylate is generated in a carboxylate exchange mixture that includes the second carboxylate source, and wherein the second lead carboxylate precipitates from the carboxylate exchange mixture.

6 . The method of claim 5 , comprising isolating the second lead carboxylate from the carboxylate exchange mixture, and dissolving and/or suspending the second lead carboxylate in water to generate the aqueous solution of the second lead carboxylate.

7 . The method of claim 1 , wherein applying the electrical bias comprises applying a voltage of approximately 3.5 volts (V) and a current between approximately 10 milliamps per square centimeter (mA/cm 2 ) and approximately 100 mA/cm 2 to the cathode and anode to generate the metallic lead.

8 . The method of claim 1 , comprising processing the metallic lead to manufacture a component of a lead-acid battery, and then manufacturing the lead-acid battery using the component.

9 . A lead recovery system, comprising:
a first reactor configured to receive and mix a lead-bearing material and a first carboxylate source to yield a first mixture, wherein the first mixture includes a first lead carboxylate that is dissolved in a liquid component of the first mixture; a second reactor configured to receive and mix the liquid component of the first mixture and a second carboxylate source to yield a second mixture, wherein the second mixture includes solid particles of a second lead carboxylate; and a third reactor configured to receive the solid particles of the second lead carboxylate, dissolve and/or suspend the solid particles of the second lead carboxylate to generate a third mixture, and apply an electrical bias to the third mixture to generate metallic lead.

10 . The system of claim 9 , wherein the third reactor comprises a rotating wheel anode configured to rotate partially submerged in the third mixture, wherein the rotating wheel anode is configured to generate the metallic lead at a surface of the rotating wheel anode while submerged in the third mixture, and configured for the metallic lead to be removed from the surface of the rotating wheel anode while emerged from the aqueous solution.

11 . The system of claim 9 , comprising a lead-acid battery processing device that is configured to receive a lead-acid battery and grind the lead-acid battery into the lead-bearing material.

12 . The system of claim 9 , comprising a first phase separation device coupled to the first and second reactors, wherein the first phase separation device is configured to:
receive the first mixture from the first reactor; separate a solid component from the liquid component of the first mixture; and advance the liquid component of the first mixture to the second reactor.

13 . The system of claim 12 , comprising a second phase separation device coupled to the second and third reactors, wherein the second phase separation device is configured to:
receive the second mixture from the second reactor; separate the solid particles of the second lead carboxylate from a liquid component of the second mixture; and advance the solid particles of the second lead carboxylate to the third reactor.

14 . The system of claim 13 , comprising a first carboxylate recovery system coupled to the second phase separation device and the first reactor, wherein the first carboxylate recovery system is configured to:
receive the liquid component of the second mixture from the second phase separation device; treat the liquid component of the second mixture to recover the first carboxylate source; and advance the recovered first carboxylate source to the first reactor to form the first mixture.

15 . The system of claim 14 , comprising a second carboxylate recovery system coupled to the second and third reactors, wherein the carboxylate recovery system is configured to:
receive a liquid component of the third mixture from the third reactor after application of the electrical bias; treat the liquid component of the third mixture to recover the second carboxylate source; and advance the recovered second carboxylate source to the second reactor to form the second mixture.

16 . The system of claim 9 , comprising a controller that includes a memory and a processor configured to provide control signals to control operations of the first, second, and third reactors.

17 . The system of claim 16 , wherein the controller is configured to provide control signals to control the application of the electrical bias to the third mixture, a temperature of the third mixture, a pH of the third mixture, a rate of stirring of the third mixture, a concentration of the second lead carboxylate in the third mixture, or a combination thereof.

18 . The system of claim 9 , wherein the first reactor, the second reactor, and the third reactor are configured to operate in a continuous manner to convert the lead-bearing material into metallic lead.

19 . A method, comprising:
processing spent lead-acid batteries to generate a lead-bearing material; leaching the lead-bearing material using a first carboxylate source to generate a leaching mixture, wherein the leaching mixture includes a dissolved first lead carboxylate; separating unleached solids from a liquid component of the leaching mixture; mixing the liquid component of the leaching mixture with a second carboxylate source to generate a carboxylate exchange mixture, wherein the carboxylate exchange mixture includes solid particles of a second lead carboxylate; separating the solid particles of the second lead carboxylate from a liquid component of the carboxylate exchange mixture; generating an aqueous solution from the solid particles of the second lead carboxylate; and applying an electrical bias to the aqueous solution of the second lead carboxylate to generate metallic lead.

20 . The method of claim 19 , wherein the leaching mixture comprises hydroxide and a peroxide to facilitate the leaching of the lead-bearing material.

21 . The method of claim 19 , comprising treating the liquid component of the carboxylate exchange mixture to regenerate a portion of the first carboxylate source, and then recycling this portion of the first carboxylate source back to generate the leaching mixture.

22 . The method of claim 19 , comprising treating the liquid component of the aqueous solution after applying the electrical bias to regenerate a portion of the second ca

Assignees

• Johnson Controls Tech Co

Inventors

• Spence Matthew A

Classifications

• H01M10/54 Primary

  Reclaiming serviceable parts of waste accumulators · CPC title

• H01M10/12

  Construction or manufacture · CPC title

• H01M4/56

  of lead · CPC title

• H01M4/38

  of elements or alloys · CPC title

• C25C7/007

  of cells comprising at least a movable electrode (C25C7/002, C25C7/02 - C25C7/06 take precedence) · CPC title