Removal of Lithium and Potassium from Aluminum Cell Electrolyte by Acid Leaching Method

The accumulation of lithium and potassium in cryolite-based aluminum electrolytes represents a growing challenge for sustainable aluminum production, leading to reduced current efficiency, increased energy consumption, and premature electrolyte replacement. This issue has become more critical as the use of medium- and low-grade bauxites with elevated alkali impurities has increased. In response, this study proposes a sustainable acid leaching process for the effective removal and recovery of lithium and potassium from spent aluminum electrolytes. The effects of leaching agent type (HCl, HNO۳, and H۲SO۴), acid dosage, temperature, and the addition of aluminum salts were systematically investigated. Among the tested reagents, sulfuric acid exhibited the highest efficiency, achieving complete removal of lithium and potassium under optimized conditions while requiring the lowest acid consumption. X-ray diffraction analysis confirmed the decomposition of LiF-containing phases and the preservation of the cryolite structure, indicating selective impurity removal without significant degradation of the electrolyte matrix. Beyond impurity control, the proposed process enables lithium recovery in a value-added form, contributing to resource conservation and waste minimization. From a sustainability standpoint, this approach reduces electrolyte waste, extends bath lifetimes, and supports circular-economy principles in aluminum electrolysis. The simplicity, high efficiency, and industrial feasibility of the process make it a promising strategy for sustainable impurity management in primary aluminum smelting operations.

کلیدواژه ها:

Aluminum Electrolyte ، Lithium Removal ، Potassium Removal ، Flux Treatment ، Hydrometallurgy