Efficient separation of impurities from pyrolusite and the enhancement of its products for improving the performance of lithium-ion batteries.

Manganese sulfate is a derivative of manganese resources with multiple applications. In addition to its traditional uses, it plays a critical role in various environmental and energy sectors. Manganese sulfate not only contributes to water treatment but also plays a significant role in the production of lithium-ion battery materials. This paper presents an innovative method for the efficient reduction and leaching of low-grade pyrolusite to produce high-purity monohydrate manganese sulfate (MnSO·HO) crystals, utilizing pyrite (FeS) as the reducing agent. This method not only enhances the production process and reduces costs, but also enables the production of high-purity monohydrate manganese sulfate crystals through the recrystallization of leachate, thus achieving the dilution heat of sulfuric acid and the recovery of wastewater. The high-purity MnSO·HO crystals produced by this method facilitate the preparation of LiFeMnPO/C lithium-ion cathode materials, which exhibit superior performance and efficiency compared to their industrial counterparts. This research advances the sustainable production of battery materials, promotes the utilization of low-grade manganese ore, contributes significantly to environmental protection and sustainable energy development, and supports the diverse applications of manganese sulfate in environmental protection technologies.