采用离子色谱法测定镍锰酸锂中硫酸根离子的含量,用盐酸和双氧水溶解试样,通过固相萃取柱净化后至离子色谱仪上进样测试,通过多次对比实验优化了试验方法。在优化的试验条件下,硫酸根在0~20.0 μg/L范围内具有良好的线性关系,线性相关系数为0.999 8。对4个不同含量的样品分别进行了11次平行测定,相对标准偏差(RSD)为1.6%~5.9%。在镍锰酸锂试样中加入硫酸根标液进行加标回收实验,硫酸根离子的加标回收率在96.1%~106.3%。与传统的硫酸钡比浊法相比,离子色谱法操作简便快捷,方法检出限低,测量范围更宽,干扰少,测定结果可靠,再现性良好,适合大批量快速样品分析。

The content of sulfate radical ion in LiNi_0.5Mn_1.5O₄ is determined by means of ion chromatography.The samples are dissolved in hydrochloric acid and hydrogen peroxide,purified by a solid phase extraction column and injected into ion chromatography for test.The experimental method is optimized through multiple comparative experiments.Under the optimal conditions,the mass concentration of sulfate radical ion in the range of 0-20.0 μg·L^-1 exhibits a good linear relationship,showing a correlation coefficient of 0.999 8.The relative standard deviations (RSD) are 1.6%-5.9% when four samples with different mass concentrations are determined for 11 times parallelly.The recovery rates of sulfate radical ions are in the range of 96.1%-106.3%.Compared with traditional double indicator titration method,the ion chromatography method runs more conveniently and faster.Meanwhile,this method has the advantages of simpler operation,lower detection limit,wider measurement range,less interference,higher precision,more reliable determination results and better reproducibility.It is suitable for rapid determination of large quantities of samples.