Electrowinning Process Flowsheets & Simulations
Explore 2 validated, solved Electrowinning simulation flowsheets in MaximaLabs — real components: water, h2so4, naoh, black_mass, li, co. Open any one directly in your browser.
Solved via: BRINE.
Battery cobalt recovery: leach, neutralize, D2EHPA Mn SX, Cyanex 272 Co SX, electrowinning
Spent NMC111 black mass is leached in sulfuric acid with the acid consumption tracked (lithium as Li₂SO₄, each transition metal as its sulfate), so the pregnant leach solution carries the residual free acid a real leach leaves. A neutralizer then titrates that liquor with 20 wt% caustic to pH 4.0 on the aqueous speciation: the caustic dose is solved, not assumed, and the heat of neutralization (55.8 kJ per mole of acid neutralized) warms the liquor; the caustic header is the supply, and what the titration does not take is returned. Two solvent-extraction circuits on the pH-isotherm chemistry follow, the common NMC arrangement: D2EHPA at pH 4.0 takes manganese into the organic while cobalt and nickel stay behind, and Cyanex 272 at pH 5.0 then takes cobalt and rejects nickel and lithium to the raffinate. The Cyanex 272 isotherms are one published measurement (Liu et al., Metals 11 (2021) 401: 0.4 M in ShellSol D70, 40 C, sulfate; pH50 cobalt 4.15, nickel 6.06), and the 1.9 pH-unit gap between them is why the cobalt organic carries about 0.6% of the nickel, against about 3% with D2EHPA at the same cobalt recovery. The loaded cobalt organic is stripped into a dilute sulfuric strip liquor, and that advance electrolyte goes to cobalt electrowinning: Faraday's law at a 90% current efficiency, 90% of the cobalt plated as cathode cobalt, the anode's oxygen and the 10% of the charge that evolves hydrogen reported as cell gas, and one mole of sulfuric acid regenerated per mole of cobalt plated.
20 unit ops • BRINE
5 0
View & openWet-process phosphoric acid: electrochemical removal of copper and cadmium
Wet-process phosphoric acid (about 42 wt% H₃PO₄, 10 kg/s) carries the metals its phosphate rock brought in: iron, zinc, nickel, copper and the cadmium that limits how the acid may be used in fertilizer. Two flow-through electrochemical cells remove the two noble enough to plate from strong acid. The first holds its cathode at -0.05 V vs SHE: copper's Nernst potential sits far above that, so copper plates at its mass-transfer limit (plug-flow law, 99% removed) while zinc, nickel, iron and cadmium, whose potentials lie below the cathode, stay dissolved. The second cell runs at -0.55 V and is told that only cadmium plates: mass transfer alone would take 99.4% of it, but at that potential and 323 K the Nernst floor holds about 2.6e-5 mol/L in solution, so the solver reports the equilibrium-limited 91% instead. Each cell's current comes from the metal's partial current and the current efficiency you give it; the copper and cadmium currents regenerate phosphoric acid (one proton per dihydrogen-phosphate counter-ion), and the rest of the charge evolves hydrogen beside the anode's oxygen, which the cell gas reports, with a flammability warning.
8 unit ops • BRINE
6 0
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