应用微波消解-ICP-AES法测定变压器油中的金属元素

Determination of Metal Elements in Transformer Oil with ICP-AES after Microwave Digestion

测量变压器油中金属元素，必须进行油样预处理。为提高样品处理效率，建立了三段微波消解法。将HNO3-H2O2作为消解用酸，结合三段微波消解法。采用电感耦合等离子体发射光谱（微波消解-ICP-AES法），测定了油样中铜、铁元素的含量。实验结果表明，两元素含量测定值的相对标准偏差均小于2％。且加标回收率为97％～101．2％，与DL/T263-2012《变压器油中金属元素的测定方法》进行对比，经t检验（α=0．05），无显著性差异。微波消解-ICP-AES法操作简便、检测快速、测量精度高。将其用于变压器油中金属元素的检测具有重要意义。

The pretreatment of transformer oil samples must be carried out before the process to determine the metal elements in transformer oil. In order to improve the efficiency of sample treatment, the three-step microwave digestion method is established. Using HNO3-H2O2 as the digestion acid and the method of ICP-AES in combination with the three-step microwave digestion, the Fe and Cu contents in the oil sample are measured. The results show that the RSDs of the two element contents are kept below 2% with the recoveries of standard addition between 98.4% and 101.2%. The analytical results obtained by the three-step microwave digestion method are compared with those by the China electric power industry standard （DL/T 263-2012 ）. Verified by t-test at the confidence level of α=0.05, no significant difference is observed between the two methods. This method is simple, rapid and accurate, which is of great significance to detect the metal elements in transformer oil.