Abstract：
The difficulty of separating Li during pyrometallurgical smelting of spent lithium-ion batteries (LIBs) has limited the development of pyrometallurgical processes. Chlorination enables the conversion of Li from spent LIBs to the gas phase during the smelting process. In this paper, the effects of four solid chlorinating agents (KCl, NaCl, CaCl2 and MgCl2) on Li volatilization and metal (Co, Cu, Ni and Fe) recovery were investigated. The four solid chlorinating agents were systematically compared in terms of the direct chlorination capacities, indirect chlorination capacities, alloy physical losses and chemical losses in the slag. CaCl2 was better suited for use as a solid chlorinating agent to promote Li volatilization due to its excellent results in these indexes. The temperature required for the release of HCl from MgCl2, facilitated by CO2 and SiO2, was lower than 500 °C. The prematurely released HCl failed to participate in the chlorination reaction. This resulted in approximately 12 % less Li volatilization when MgCl2 was used as a chlorinating agent compared to when CaCl2 was used. In addition, the use of KCl as a chlorinating agent decreased the chemical dissolution loss of alloys in the slag. The performance of NaCl was mediocre. Finally, based on evaluations of the four indexes, recommendations for the selection and optimization of solid chlorinating agents were provided.
摘要：
在废旧锂离子电池（LIB）的火法冶炼过程中分离Li的困难限制了火法冶金工艺的发展。氯化使Li在熔炼过程中从废LIB转化为气相。在本文中,四种固体氯化剂(KCl，NaCl,CaCl2和MgCl2)对Li的挥发和金属(Co,Cu,研究了Ni和Fe）的回收率。系统地比较了四种固体氯化剂的直接氯化能力，间接氯化能力，合金在炉渣中的物理损失和化学损失。CaCl2由于其在这些指标中的优异结果,更适合用作固体氯化剂以促进Li的挥发。由CO2和SiO2促进的从MgCl2中释放HCl所需的温度低于500°C。过早释放的HCl未能参与氯化反应。与使用CaCl2时相比,当MgCl2用作氯化剂时,这导致Li挥发减少约12%。此外,使用KCl作为氯化剂减少了合金在炉渣中的化学溶解损失。NaCl的性能一般。最后,根据对四个指标的评估，为固体氯化剂的选择和优化提供了建议。
