高性能电池级四氧化三锰制备技术的研究及产业化应用
Research and Industrial Application of High-Performance Battery-Grade Manganese Tetroxide Preparation Technology

以高纯硫酸锰溶液为原料，采用空气氧化法制备四氧化三锰，研究了反应温度、反应时间、Mn²⁺浓度、碱液浓度即pH对四氧化三锰产品主要性能指标锰含量和振实密度的影响，并对四氧化三锰产品进行了粒度和微观形貌分析。研究结果表明，电池级四氧化三锰的适宜反应条件为：体系中pH 9.4，初始硫酸锰溶液浓度1.3 mol·L^？1，反应温度70℃，反应时间25 h。在此工艺条件下，制备得到的四氧化三锰Mn含量在71.40%以上，振实密度在2.71 g·cm^？3以上，粒度呈正态分布，中位径D₅₀为10 μm左右，产品结构紧密，颗粒形貌为类球形，满足生产高端锰酸锂对原材料的要求，本研究成果已在广西锰华公司实现了规模产业化应用，产能达到10,000吨电池级四氧化三锰/年，成为了广西生产电池级四氧化三锰的龙头企业。
Using high-purity manganese sulfate solution as the raw material, manganese tetroxide (Mn₃O₄) was synthesized via the air oxidation method. The effects of reaction temperature, reaction time, Mn²⁺ concentration, alkali concentration (i.e., pH), and other parameters on the manganese content and tap density of the Mn₃O₄ product were systematically investigated. Additionally, particle size distribution and microstructure analysis of the product were conducted. The results indicate that the optimal reaction conditions for producing battery-grade Mn₃O₄ are as follows: pH 9.4 in the system, initial manganese sulfate concentration of 1.3 mol·L^？1, reaction temperature of 70？C, and reaction duration of 25 hours. Under these conditions, the prepared Mn₃O₄ exhibits a manganese content exceeding 71.40%, a tap density above 2.71 g·cm^？3, and a normal particle size distribution with a median particle size (D₅₀) of approximately 10 μm. The product demonstrates a compact structure and quasi-spherical morphology, meeting the requirements for raw materials in high-performance lithium manganate production. This research achievement has been successfully scaled up for industrial application at Guangxi Menghua Co., Ltd., achieving an annual production capacity of 10,000 tons of battery-grade Mn₃O₄, establishing the company as a leading enterprise in Guangxi for battery-grade Mn₃O₄ manufacturing.