Recovery of lithium from an acid solution

Abstract

Methods of recovering lithium from a lithium source or a lithium-containing material using low pH solutions and membrane technologies to purify and concentrate the recovered lithium. The lithium sources may include a spent lithium-ion battery/cell, a lithium-containing mineral deposit, or other lithium containing materials. The processes described herein recovery the lithium after digestion of the lithium-containing material with a low pH solution through one or more acid-stable, semipermeable membranes.

1 - 20 . (canceled) 
     
     
         21 . A method of recovering graphite from a lithium ion cell or battery, the method comprising:
 disassembling a lithium ion cell or battery to separate an anode from a cathode to form a disassembled lithium ion cell or battery;   mixing the disassembled lithium ion cell or battery with an acid at a temperature of about 10° C. to about 100° C. to form an acidic solution including graphite, lithium, and optionally one or more of soluble organics, soluble metals, and suspended solids;   wherein the acid has a pH of about 2.5 or less and includes hydrochloric acid, sulfuric acid, nitric acid, acetic acid, citric acid, or combinations thereof; and   separating the graphite from the acidic solution.   
     
     
         22 . The method of recovering graphite of  claim 21 , wherein the dissembling including removing a shell surrounding the anode, the cathode, and an electrolyte of the lithium ion cell or battery. 
     
     
         23 . The method of recovering graphite of  claim 21 , wherein the lithium ion cell or battery is a spent lithium-ion cell or battery. 
     
     
         24 . The method of recovering graphite of  claim 21 , wherein the acid includes hydrochloric acid, sulfuric acid, nitric acid, or combinations thereof and has an acid concentration of about 0.5 to about 30 weight percent in an aqueous solution with a pH of about 1 or less. 
     
     
         25 . The method of recovering graphite of  claim 21 , wherein the mixing is for about 1 minute to about 120 minutes. 
     
     
         26 . The method of recovering graphite of  claim 21 , wherein the mixing is at a temperature of about 50° C. to about 70° C. 
     
     
         27 . The method of recovering graphite of  claim 21 , further comprising delivering the acidic solution to an ultrafiltration membrane to separate a majority of the suspended solids from a permeate including at least one or more of the acid, the lithium, the soluble organics, and the soluble metals. 
     
     
         28 . The method of recovering graphite of  claim 27 , wherein the ultrafiltration membrane has a pore size of about 0.01 microns to about 0.5 microns and is operated at about 10 to about 100 psi. 
     
     
         29 . The method of recovering graphite of  claim 21 , wherein the lithium ion cell or battery includes a metal oxide cathode, a metal foil anode, an electrolyte, and a polymeric separator. 
     
     
         30 . The method of recovering graphite of  claim 29 , wherein the metal foil anode includes graphite thereon. 
     
     
         31 . The method of recovering graphite of  claim 29 , wherein the metal oxide cathode is an aluminum foil having a coating of cobalt nickel alloy, lithium cobalt oxide, lithium iron phosphate, lithium manganese oxides, lithium fluoride phosphate, lithium moly oxide, nickel cobalt oxide, or combinations thereof. 
     
     
         32 . The method of recovering graphite of  claim 29 , wherein the electrolyte is a polymeric organic, organic solvent, phosphate, fluoride, a lithium salt, phosphate fluoride, or combinations thereof. 
     
     
         33 . The method of recovering graphite of  claim 29 , wherein the polymeric separator is polypropylene, polyethylene, or combinations thereof. 
     
     
         34 . An acid treated graphite obtained from a spent lithium-ion cell or battery, the acid treated graphite obtained by disassembling a spent lithium ion cell or battery to separate an anode from a cathode to form a disassembled lithium ion cell or battery, mixing the disassembled lithium ion cell or battery in an acid to form an acidic solution, the mixing at a temperature of about 10° C. to about 100° C. and the acidic solution including graphite, lithium, and one or more of soluble organics, soluble metals, and suspended solids and wherein the acid has a pH of about 2.5 or less and includes hydrochloric acid, sulfuric acid, nitric acid, acetic acid, citric acid, or combinations thereof, and separating the acid treated graphite from the acidic solution. 
     
     
         35 . The acid treated graphite of  claim 34 , wherein the acid includes hydrochloric acid, sulfuric acid, nitric acid, or combinations thereof and has an acid concentration of about 0.5 to about 30 weight percent in an aqueous solution with a pH of about 1 or less. 
     
     
         36 . The acid treated graphite of  claim 34 , wherein the spent lithium ion cell or battery includes a metal oxide cathode, a metal foil anode, an electrolyte, and a polymeric separator. 
     
     
         37 . The acid treated graphite of  claim 36 , wherein the metal foil anode includes graphite thereon. 
     
     
         38 . An acidic solution for recovery of graphite from a lithium ion cell or battery, the acidic solution including an acid and a spent lithium ion cell or battery providing to the acidic solution lithium, graphite, and one or more of soluble organics, soluble metals, and suspended solids, the acid includes hydrochloric acid, sulfuric acid, nitric acid, or combinations thereof and has an acid concentration of about 0.5 to about 30 weight percent in an aqueous solution with a pH of about 1 or less. 
     
     
         39 . The acidic solution of  claim 38 , wherein the spent lithium ion cell or battery of the acidic solution includes a metal oxide cathode, a metal foil anode including the graphite, an electrolyte, and a polymeric separator. 
     
     
         40 . The acidic solution of  claim 38 , further including the soluble metals selected from the group consisting of calcium, magnesium, zinc, copper, aluminum, iron, phosphate, fluoride, rare earth metals, cobalt, nickel, or combinations thereof.