Research progress of technology of lithium extraction

Abstract

Lithium (Li) is a core strategic metal in the new energy industry. Due to its wide range of applications in various fields, the demand from the resource market is growing year by year. At present, Li is mostly extracted from lithium minerals (solid lithium ore and liquid lithium ore), seawater and spent lithium-ion batteries (LIBs). This paper focuses on the lithium extraction process of various lithium resources, expounds its reaction mechanism and application performance, and puts forward the possible future development direction. The extraction of lithium from solid lithium ores by the acid process has good practical applications but poor environmental sustainability. Additionally, the proportion of lithium resources of liquid lithium ore (brine) is greater than that of solid lithium ore, and extracting lithium from brine is the most valuable choice at present. The Li content in the brine is typically low. Lithium extraction with inorganic adsorbent is the most advanced method at present. Different techniques include evaporative crystallization, precipitation, solvent extraction, adsorption with organic and biological adsorbent, membrane separation, and electrochemical methods. However, most of the technologies with favorable economic benefits and high efficiency are still difficult to achieve large-scale industrialization. Therefore, it is still a great challenge to develop an economical, environmentally friendly, efficient and practical technology for extracting lithium from brine. Furthermore, with the rise and vigorous development of the LIBs market, the treatment and recycling of spent LIBs has become a major problem. According to the research, it is feasible to extract lithium from spent LIBs and achieve industrialization and recycling. Therefore, research on lithium extraction from spent LIBs is also the key to increasing the supply of lithium resources and achieving resource recycling.