变压器油中T501抗氧化剂电化学特性研究及测定

The electrochemical properties and determination of T501 antioxidant in transformer oil

利用线性扫描伏安法,通过单因素实验,研究了变压器油中T501抗氧化剂的电化学特性。并结合密度泛函理论对其进行了分析探讨,优化了实验条件,如：工作电极的材料和大小、电解质溶液的组成和浓度等;确定了实验的最佳条件：直径6mm石墨电极为工作电极,KOH-乙醇溶液（KOH浓度0.15 mol/L,含水量的体积分数1%）为电解质溶液,进而建立了一种快速准确的测定变压器油中T501抗氧化剂含量的新方法。研究结果表明,在优化条件下,在变压器油T501使用浓度范围内（质量分数0.05%~0.50%）,T501浓度C与峰电流Ip（μA）之间呈现良好的线性关系,检出限（S/N=3）为0.045%,回收率为98.67%~102.00%。本方法具有较高可靠性和实用性,在保证准确性的前提下,大大提高了变压器油中T501含量测定的效率。

Abstract： The electrochemical properties of T501 antioxidant in transformer oil were inves- tigated comprehensively by using linear sweep voltammetry（LSV） and single factor exper- ira, and analyzed by combining density functional theory（DFT） calculations. The experi- mental conditions were optimized, such as the material and size of working electrode, the composition and concentration of electrolyte solution. The best experimental conditions were determined, the working electrode was a 6 mm-diameter graphite electrode electrode, the alcoholic KOH solutions were used as electrolytes, and the concentrations of KOH were controlled to be 0.15 mol/L, the water content（volume fraction） was controlled to be 1%. A new method was established to detect the T501 antioxidant content in transformer oil rapidly and accurately. The results showed that there was a good linear relationship between the oxidation peak current Ip （μA） and the concentration（mass fraction） of T501 antioxi- dant in transformer oil among 0.05%-0.50% under the optimal conditions. The detectionlimit （S/N=3） was 0.045%, and the standard addition recovery was 98.67%-102.00%. This method was of high reliability and practicability, and greatly improved the efficiency of the determination of T501 content in transformer oil on the premise of the accuracy.