反相可切换亲水性溶剂液-液微萃取/电感耦合等离子体质谱法测定变压器油中铜和铁离子含量  

Determination of Contents of Copper and Iron Ions in Transformer Oil by Inductively Coupled Plasma Mass Spectrometry with Reversed Phase Switchable Hydrophilic Solvent Liquid-Liquid Microextraction

作　　者：付宇超 杨珍[1,2] 李吟霜 李海燕 FU Yu-chao;YANG Zhen;LI Yin-shuang;LI Hai-yan(College of Chemistry and Materials Science,South-Central Min Zu University,Wuhan 430074,China;Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission,South-Central Min Zu University,Wuhan 430074,China)

机构地区：[1]中南民族大学化学与材料科学学院,湖北武汉430074 [2]中南民族大学分析化学国家民委重点实验室,湖北武汉430074

出　　处：《分析测试学报》2022年第7期1078-1083,共6页Journal of Instrumental Analysis

基　　金：中央高校基本科研业务费专项资金项目(CZY19037)。

摘　　要：以电感耦合等离子体质谱(ICP-MS)为检测手段,研究了反相可切换亲水性溶剂液-液微萃取(SHS-LLME)同时分离富集变压器绝缘油中Cu^(2+)和Fe^(3+)的方法。优化的萃取条件为:以50μL三乙胺(TEA)萃取25 mL变压器油样,0.60 mol/L硝酸溶液为触发剂,TEA和HNO_(3)摩尔比为1∶1.5,涡旋萃取反应5 min,亲水切换反应5 min,经离心分离后,取水萃取相直接进样测定。变压器油中Cu^(2+)和Fe^(3+)的质量浓度在0.100~10.0μg/L范围内线性关系良好,线性系数(r^(2))均为0.9996,检出限分别为16.8 ng/L和29.0 ng/L,富集倍数分别为23.7和24.1倍。对模拟老化变压器油样中Cu^(2+)和Fe^(3+)的含量进行测定,其加标回收率为93.3%~112%,相对标准偏差(n=6)为3.6%~5.6%。该文所建立的样品前处理方法与现行标准所用的灰化法无显著性差异,可实现老化变压器油中痕量Cu^(2+)和Fe^(3+)的同时测定。Increase in the concentration of metal copper and iron ions in the insulation oil for running transformer not only leads to the deepening of the corrosion of the high-voltage copper windings and iron cores immersed in the transformer oil and reduction of insulation performance of the transformer oil,but also causes the increase in the insulation aging ability of transformer oil-paper of metal ion catalysis.In order to track the concentration of copper and iron ions in the transformer oil in operation,and reduce sudden transformer insulation failures caused by the accelerated aging of transformer oil-paper insulation,an inductively coupled plasma mass spectrometry(ICP-MS)with reverse phase switchable hydrophilic solvent liquid-liquid microextraction was developed for the simultaneous separation,enrichment and determination of Cu^(2+) and Fe^(3+) in transformer insulating oil.The switchable hydrophilic solvent triethylamine(TEA)was used as the extractant,and nitric acid solution was used as the trigger.The extraction conditions were optimized as follows:50μL of TEA was used to extract 25 mL of transformer oil sample,the molar ratio of TEA to HNO_(3) was 1∶1.5,the concentration of HNO_(3)was 0.60 mol/L,the reaction time of vortex extraction and the hydrophilicity switching reaction were both 5 min,the lower water extract phase could be directly injected for determination after centrifugation was performed at 4500 r/min for 5 min.There were good linearities for Cu^(2+) and Fe^(3+) in the range of 0.100-10.0μg/L,with their correlation coefficients(r2)of 0.9996.The detection limits for Cu^(2+) and Fe^(3+) were 16.8 ng/L and 29.0 ng/L,respectively,and the enrichment factors were about 24 times.The concentration of Cu^(2+) and Fe^(3+) in the oil samples of the simulated aging transformer were determined.And the spiked recoveries of Cu^(2+) and Fe^(3+) ranged from 93.3%to 112%,with relative standard deviations(RSDs)of 3.6%-5.6%.There is no significant difference between the sample pretreatment method established in th

关 键 词：反相可切换亲水性溶剂 液-液微萃取 铜和铁离子 变压器油 电感耦合等离子体质谱(ICPMS) 

分 类 号：O657.63[理学—分析化学] O614.12[理学—化学]