Analysis of Lanthanum and Cobalt Leaching Aimed at Effective Recycling Strategies of Solid Oxide Cells

Lanthanum and cobalt are Critical Raw Materials components of Solid Oxide Cells—SOCs electrodes. This review analyses lanthanum leaching from waste materials (e-waste, batteries, spent catalysts), aiming to provide a starting point for SOC recycling, not yet investigated. The literature was surveyed with specific interest leaching, the first phase hydrometallurgy recycling. Most references (86%) were published after 2012, an higher (85%) cobalt. Inorganic acids prevailing (>80%) agents, particularly lanthanum, while processes using organic mostly involved experimental conditions adopted more diluted (median 0.55 M 1.4 cobalt) compared inorganic value 2 both metals). Organic required solid liquid ratio (200 g/L), ones (100 g/L) solubilize opposite happened (20 vs. 50 g/L). process temperature didn’t change considerably solvent (45–75 °C 75–88 cobalt). contact time than 3–4 h 75–85 min). Specific recycling crucial support SOCs chain in Europe, this can help define existing challenges future perspectives.