The success story of lithium-ion batteries in the field of electromobility but also portable devices is undisputed and will continue to make a significant contribution to decarbonization in the future. However, in line with the idea of circular economy, efficient and sustainable recycling strategies for spent lithium-ion batteries are mandatory. The need to recover the valuable metals Co, Ni, Mn and Li with high quality and efficiency is therefore of great importance. Due to the basic chemical properties of e.g. lithium, efficient recovery is often only possible by hydrometallurgical methods. Furthermore, hydrometallurgy exhibits significant advantages such as low-emission process design and low energy requirements. Conventional hydrometallurgical methods employ strong inorganic acids to dissolve the valuable metals. However, this leads to a significant salt load in the process effluents and to an increased CO2 equivalent due to the production of the chemicals applied. Therefore, the substitution
of these with organic acids appears to be a significant improvement with respect to the challenges addressed. The SeLiReco (Selective Lithium Recovery) process similarly originally built on leaching with sulfuric acid. Subsequently, selective precipitation steps enable the valuable metals to be recovered in high quality. Particularly remarkable is the possibility of recovering lithium as lithium
phosphate in a high quality and with an efficiency of 90 %. The further development of this process to SeLiReco 2.0 included the substitution of sulfuric acid by citric acid, which has a significantly lower CO2 equivalent in its production. It could be shown that despite the application of the weaker acid,
efficient leaching can be demonstrated. Furthermore, the feasibility as well as the efficiency of the subsequent precipitation steps could also be confirmed. This adaptation of the original SeLiReco process thus leads to a more sustainable design of the process and maintains the high standards of the recovered products.