电位滴定测定富锂锰基正极材料中锰

采用盐酸、硝酸溶解样品,加入焦磷酸钠溶液并调节溶液pH为6.0~7.0。用高锰酸钾标准溶液滴定至电位滴定仪上,根据消耗的高锰酸钾标准溶液的体积计算样品中的锰含量。探究了焦磷酸钠用量、溶液pH、共存元素等对测定锰含量的影响。在最优的实验条件下,方法的相对标准偏差在0.13%~0.22%之间,加标回收率在99.8%~100.5%之间。本方法是富锂锰基正极材料中质量分数10%~60%的锰测定的理想方法。

Determination of manganese in lithium-rich manganese-based cathode materials by potentiometric titration

The sample was dissolved by hydrochloric acid and nitric acid,then sodium pyrophosphate solution wasand hydrochloric acid or sodium carbonate solution was added to adjust the pH to 6.0~7.0.Manganese content in lithium-rich manganese cathode materials was tested by potentiometric titration,and the content value was calculated according to the consumed potassium permanganate standard solution.Besides,the influence of sodium pyrophosphate amount,pH and coexistence elements on the measurement of manganese content was investigated.Under the optimal conditions,the relative standard deviations were 0.13%~0.22%,with the recoveries of the spiked standard of 99.8%~100.5%.An ideal method for the determination of manganese content with the mass fraction of 10%~60% in lithium-rich manganese cathode materials was provided.