The data of the article"A Novel Multistage Synergistic Roasting-Leaching-Adsorption Strategy for Ef-ficient Lithium Extraction from Coal Fly Ash"

With China producing a vast amount of coal fly ash rich in lithium each year, the extraction of this resource is of great importance for supporting the sustainable development of the new energy sector. However, the low lithium content in coal fly ash, along with its occurrence in chemically inert glass phases, makes efficient and selective ex-traction challenging via conventional approaches. In this study, a multi-stage synergistic strategy “roasting-alkali leaching-adsorption” was proposed to enhance lithium recovery. The Si-O-Al bonds in aluminosilicate glass phase of coal fly ash were effectively disrupted by calcination at 900℃ for 2 h in the presence of sodium sulfate. Then, the resulting calcine was subjected to alkaline leaching using 1 mol·L-1 NaOH at 70℃ with a liquid-to-solid ratio of 5:1, leading to the selective release of lithium ions. Finally, lithium was efficiently separated from impurities in the leachate by employing lithium titanate as a selective adsorbent. This novel process achieved an overall lithium re-covery of 73.20% and a lithium/impurity separation coefficient greater than 163, thereby realizing precise extraction of lithium from coal fly ash. The proposed method offers a promising strategy for the high-value utilization of such unconventional lithium resources.