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Lithium extraction from a cookeite-bearing bauxite using mixed chloride roast-leaching: Geochemical characterization and process optimization.

Senapati S, Rath SS, Kumar TV, Angadi SI, Sreenivas B.

POWDER TECHNOLOGY

https://doi.org/10.1016/j.powtec.2026.122267 

This research is part of the CSIR Fast Track Translational Mission Mode project on lithium recovery from primary Indian resources, undertaken collaboratively by CSIR-IMMT, CSIR NGRI, CSIR-NML, and CSIR-CECRI. The project aims to characterize Indian lithium ores, develop extraction methodologies, and enable the manufacturing of Li-ion cells. The present study, published in Powder Technology, represents a joint effort between CSIR-NGRI and CSIR-IMMT. CSIR-NGRI focused on the characterization of lithium-enriched pisolitic bauxites from Reasi, Jammu, while CSIR-IMMT carried out lithium extraction from these ores. Mineralogical investigations identified cookeite—a lithium-aluminum phyllosilicate mineral of the chlorite group with the chemical formula LiAl₄(Si₃Al)O₁₀(OH)₈—as the primary lithium-bearing phase. LA-ICP-MS analysis revealed that lithium concentration is higher in the kaolinitic matrix compared to the kaolin present in the pisolite cores, whereas the Fe rich oxide rims of the pisolites contain the lowest lithium concentration. A chloridizing roasting process followed by water leaching was employed for lithium extraction. Among various additives tested, a NaCl-KCl mixture demonstrated superior performance, achieving over 99% Li₂O recovery from an initial concentration of 0.11% Li₂O. Optimal conditions included a roasting temperature of 800 °C, duration of 1 hour, an additive-to-ore ratio of 2.92, and a NaCl-to-KCl ratio of 2.21. Statistical analysis using Response Surface Methodology (RSM) identified the additive-to-ore ratio as the most significant parameter (CSIR-Integrated SkillInitiative) influencing the roast-leach process, followed by the NaCl-to-KCl ratio and roasting time with comparatively lower impact. This study represents one of the first systematic efforts to characterize and recover lithium from Indian bauxite resources and contributes to the broader global research on lithium extraction from clay-based deposits.

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