An Effective Lithium Extraction Route from Lepidolite

The conditions for efficient lithium extraction from lepidolite were studied. The experiments indicated that the best molar ratio of Li in lepidolite to Na2SO4 mass ratio during roasting was 1:6. The extraction of Li was >90% after 0.5 h of roasting at 750 degrees C. The extraction of Li was essentially constant when roasted at temperatures over 700 degrees C. With smaller particle sizes of lepidolite (in the range of 100-200 mu m), it is possible to achieve a high efficiency of Li extraction even at a low temperature of 700 degrees C and a short holding time of 30 min. The efficient roasting condition is easily adapted in industrial application.