Lithium slag (LS) is a process residue that is derived from lithium production in industrial settings. The process of obtaining lithium involves the extraction and concentration of lithium-rich brines followed by the conversion of lithium compounds and finally, the heat treatment of the purified compounds to obtain the final lithium form. The heat treatment step can result in the formation of lithiated compounds in the form of slag.
Lithium slag is one of the by-products of lithium processing and contains various concentrations of lithium, aluminum, sodium and other materials. The use of the bath process to obtain lithium results in the formation of aluminum rich slag, which is mainly composed of lithium, aluminum and sodium silicates that are insoluble in water. The aluminum rich slag is then further processed at high temperatures which results in the formation of lithium-rich slag. The metallic elements present in the lithium-rich slag can be extracted through smelting or leaching processes.
The use of lithium slag has been gaining attention in the past years due to its potential applications in various industries. The slag has been used as a preservative and sealing material in cookware and paper coatings, as well as in construction materials such as road fill and aggregates. In addition, it has been utilized as a glass manufacturing flux, a soil conditioning agent, an additive in cement and a concrete hardener. Moreover, lithium slag can also be used as a catalyst in a variety of industrial processes and as an adsorbent for the removal of hazardous substances, such as heavy metals, from wastewater.
Although the utilization of lithium slag is growing, there are some challenges that need to be addressed in order to increase and promote its usage. First, the toxic nature of the slag and its potential leaching into the environment is an issue that needs to be addressed. Second, the slag must be further processed in order to remove trace amounts of poisonous heavy metals before it can be used in various applications. Finally, the cost associated with the recovery and processing of lithium slag needs to be reduced in order for it to be a viable option in different markets and industries.
One of the main ways to reduce the cost of lithium slag processing is to apply the technology of pyrometallurgy. This technology combines the use of furnace, lasers and other chemical processes with other technologies in order to efficiently recover valuable metal resources with high economic value from lithium slag. Additionally, this technology has the advantage of being able to reduce the amount of waste generated during the process.
In conclusion, lithium slag has recently gained increasing attention due to its potential applications in various industries. Its utilization is expected to continue growing in the coming years. However, there are some challenges that need to be addressed, such as the toxic nature of the slag and its potential leaching into the environment, as well as the need for further processing and the associated costs. The application of pyrometallurgy can help to address some of these challenges and thus reduce the cost of lithium slag processing in order to make it a viable option for different markets and industries.
