Recovery of LiCoO2 and graphite from spent lithium-ion batteries by Fenton reagent-assisted flotation

In this paper, a Fenton reagent assisted flotation process is developed to recover valuable electrode materials LiCoO2 and graphite from spent lithium-ion batteries (LiBs). At room temperature, effect of key parameters for Fenton reaction such as the ratios of H2O2/Fe2+ (40-280) and liquid-solid (25-100) are investigated to determine the most efficient conditions of surface modification of electrode materials by Fenton reagent. The modified electrode materials are separated by flotation operation to recover the cathode material and anode materials respectively. The results show that in the optimum conditions that the Fe2+/H2O2 ratio is 1:120, and the liquid-solid ratio is 75:1, most of the organic outer layer coated on the surface of electrode materials can be removed. After modified by Fenton reagent, the original wettability of LiCoO2 and graphite is regained. The −0.25 mm crushed products of spent LiBs can be separated into LiCoO2 concentrate and graphite concentrate by flotation process efficiently.