Recycling of Precious Metals from the Waste of Lithium-Ion Batteries

The process of recovering metals from spent lithium-ion batteries is difficult due to the complexity of the metal components. Therefore, the separation and extraction of metal ions from the leaching solution of spent lithium-ion batteries requires a set of hydrometallurgical processes. In this research, precipitation and solvent extraction processes have been used to the final recovery of metals. Initially, 96.5% of manganese ions were precipitated by applying potassium permanganate with the molar ratio of manganese ions to potassium permanganate: 2 and pH: 2. Then, via dimethylglyoxime in molar ratio of nickel ions to dimethylglyoxime: 0.5, and pH: 5, 96% nickel recovered, approximately. Subsequently, using 30 v/v% D2EHPA and 5 v/v% TBP respectively as an extractant and a modifier of the organic phase, and under optimal conditions of Vo/Va: 1, pH: 5, temperature 25 ºC, time 20 min and mixing speed 400 rpm, it is possible to achieve 93.38% cobalt extraction efficiency and also control the loss of lithium at 16.74%. Finally, in the molar ratio of lithium ions to sodium carbonate: 0.7, temperature 100 ºC, time 40 min, mixing speed 400 rpm and the pH: 12, the lithium precipitation efficiency reached to 98.84%.