Extraction of Lithium from Petalite Ore by Chloride Sublimation Roasting

Semi-industrial tests of the chloride sublimation technology for extracting lithium from petalite ore with concurrent production of cement clinker have been carried out. The main technical and economic indicators of production of lithium carbonate have been determined. Chloride sublimation roasting method allows combining ore roasting and lithium sublimation with the process of obtaining (roasting) Portland cement clinker. Thus, it becomes possible to distribute energy costs for high-temperature roasting over a much larger volume of products: clinker and lithium salts. The recovered lithium in the form of lithium chloride vapor is captured by an aqueous absorbing solution, which has a much smaller volume as compared to the volumes of leaching solutions in lime, sulfuric acid, or autoclave alkaline technologies. Correspondingly, the flows of the solutions being processed are reduced, which significantly saves reagents and energy during their processing and considerably reduces the capital costs of tank equipment. Owing to the high content of aluminum and silicon oxides in lithium aluminosilicate ores, it is possible to use them in the production of cement clinker instead of the clay component of the charge.