title: Recovery of cobalt from spent lithium-ion batteries using supercritical carbon dioxide extraction.
abstract: Continuing technological development decreases the useful lifetime of electronic equipment, resulting in the generation of waste and the need for new and more efficient recycling processes. The objective of this work is to study the effectiveness of supercritical fluids for the leaching of cobalt contained in lithium-ion batteries (LIBs). For comparative purposes, leaching tests are performed with supercritical CO2 and co-solvents, as well as under conventional conditions. In both cases, sulfuric acid and H2O2 are used as reagents. The solution obtained from the supercritical leaching is processed using electrowinning in order to recover the cobalt. The results show that at atmospheric pressure, cobalt leaching is favored by increasing the amount of H2O2 (from 0 to 8% v/v). The use of supercritical conditions enable extraction of more than 95wt% of the cobalt, with reduction of the reaction time from 60min (the time employed in leaching at atmospheric pressure) to 5min, and a reduction in the concentration of H2O2 required from 8 to 4% (v/v). Electrowinning using a leach solution achieve a current efficiency of 96% and a deposit with cobalt concentration of 99.5wt%.
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Universidade Federal de Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil. Electronic address: Dbertuol@gmail.com.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Bertuol
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Universidade Federal de Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Caroline M
authors.initials: CM
authors.lastname: Machado
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Universidade Federal de Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Mariana L
authors.initials: ML
authors.lastname: Silva
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Universidade Federal de Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Camila O
authors.initials: CO
authors.lastname: Calgaro
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Universidade Federal de Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Guilherme L
authors.initials: GL
authors.lastname: Dotto
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Universidade Federal de Santa Maria - UFSM, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Eduardo H
authors.initials: EH
authors.lastname: Tanabe
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D003035:Cobalt / Q000032:analysis / Q000302:isolation & purification*; D011211:Electric Power Supplies; D059029:Electronic Waste / Q000032:analysis*; D006861:Hydrogen Peroxide / Q000737:chemistry; D008094:Lithium; D059027:Recycling / Q000379:methods*; D013464:Sulfuric Acids / Q000737:chemistry; D018505:Waste Management / Q000379:methods*
chemical_list: D013464:Sulfuric Acids; D002245:Carbon Dioxide; D003035:Cobalt; D008094:Lithium; D006861:Hydrogen Peroxide; C033158:sulfuric acid
keywords: Cobalt; Fast extraction; Lithium ion batteries; Recycling; Supercritical fluids