CPC H01M 10/54 (2013.01) [C22B 1/005 (2013.01); C22B 7/003 (2013.01); C22B 7/007 (2013.01); C22B 23/0415 (2013.01); C22B 23/0492 (2013.01); C22B 26/12 (2013.01); C22B 47/00 (2013.01); H01M 6/52 (2013.01)] | 14 Claims |
1. A process for the recovery of metals M from a Li-containing starting material, wherein M comprises Ni and Co, comprising the steps of:
Step 1: Providing said starting material, comprising Li-ion batteries or their derived products;
Step 2: Removing Li in an amount of more than the maximum of (1) 30% of the Li present in said starting material, and (2) a percentage of the Li present in said starting material determined to obtain a Li:M ratio of 0.70 or less in a subsequent acidic leaching step, by using either one or more of:
a pyrometallurgical smelting process comprising heating and introducing a reducing agent and slag-formers, thereby producing one or more of a Li-bearing slag phase and Li-fumes, and a Li-depleted Ni—Co-bearing phase susceptible to be acid-leached;
a thermal treatment process comprising heating and introducing a reducing agent, thereby producing a Ni—Co-bearing residue containing at least one water-soluble Li-compound, and removing said at least one Li-compound by washing with an aqueous solution, thereby obtaining a Li-depleted Ni—Co-bearing residue susceptible to be acid-leached;
a hydrometallurgical leaching process comprising introducing an aqueous or acidic solution, thereby leaching Li from said starting material, wherein Ni and Co are at least partially insoluble, and solid-liquid separation, thereby obtaining a Li-depleted Ni—Co-bearing residue susceptible to be acid-leached;
Step 3: Subsequent leaching using relative amounts of Li-depleted Ni—Co-bearing material, obtained in step 2, and a mineral acid, thereby obtaining a Ni- and Co-bearing solution; and,
Step 4: Crystallization of Ni, Co, and optionally Mn, wherein step 4 is performed by lowering the temperature of the Ni- and Co-bearing solution and/or by removing water from the Ni- and Co-bearing solution and/or by solvent displacement crystallization.
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