高温水解-离子色谱法测定钴酸锂中氯

Determination of Chloride in Lithium Cobalt Oxide by High Temperature Combustion Hydrolysis-Ion Chromatography

使用高温水解-离子色谱法对钴酸锂中痕量的氯进行分析测定。样品在1 100℃高温下通入氧气与水蒸气进行水解反应,生成氯化氢气体随载气带出,经冷凝后接收,并通过离子色谱法对氯的含量进行测定。以NaHCO3（4.5mmol/L）与Na2CO3（2.7mmol/L）的混合溶液为淋洗液,经SH-AG-1保护柱及SH-AC-1分离柱分离,Cl-在0.05~5.00mg/L范围内浓度与峰面积呈线性关系,检出限（3S）为0.010mg/L。方法测定氯的加标回收率在92%~96%,相对标准偏差（n=11）在3.0%~5.3%,方法准确、可靠。

A new method for the determination of chloride in lithium cobalt oxide accurately was developed by high temperature combustion hydrolysis-ion chromatography. The hydrogen chloride gas was generated by hydrolysis reaction with the sample. Oxygen and steam at 1 100 ℃ was carried over with carrier gas. The content of chloride was determined by ion chromatography after the hydrogen chloride gas was received by condensation. The optimized experimental conditions were obtained as follows., a mixed solution of 4.5 mmol/L NaHCO3 and 2.7 mmol/L Na2COa mixture as eluent, SH-AG-1 as protect column and SH-AC-1 as separation column. The content of chloride ion in the range of 0.05 - 5.00 mg/L was linear to the peak area. The detection limit （3s） was 0. 010 mg/L. The recovery was 92%~96% with 3.0%-5.3% RSD＇s （n=ll）. This method has been proved to be accurate for the determination of trace chlorine in lithium cobalt oxide.