2-硫代巴比妥酸显色法检测变压器油中糠醛的研究

Determination of Furfural Content in Transformer Oil with 2-Thiobarbituric Acid Colorimetry

通过配制不同浓度的糠醛溶液、油样萃取液、BHT溶液,采用光谱法检测发现变压器油中含有大量抗氧化剂二丁基羟基甲苯(BHT),BHT的存在严重干扰了糠醛在275nm处的吸收峰,无法通过直接检测油样萃取液而得知糠醛浓度。故通过在油样萃取液中加入一定量的2-硫代巴比妥酸(TBA)溶液,利用TBA与糠醛发生的显色反应来间接测量糠醛的浓度。结果表明:2-硫代巴比妥酸(TBA)溶液能有效排除BHT的干扰,TBA能与糠醛发生显色反应,在390 nm处出现新的吸收峰,峰高与糠醛浓度呈现良好的线性关系,说明TBA显色法能有效检测出变压器油中糠醛含量,同时很好克服了传统高效液相法过程繁琐、测量时间长等缺点,为变压器油中糠醛浓度检测提供了一种新思路。

Different concentration of furfural solution, extraction of transformer oil, and butylatedhydroxy- toluene （BHT） were prepared, and it was found that there was so much BHT in the transformer oil by spectroscopy. The existence of BHT would interfere the absorption peak of furfural at 275 nm, leading to the furfural content can＇t be obtained by detecting the extraction of transformer oil directly. So TBA （2-thiobarbituric acid） solution was added into the extraction of transformer oil, and the furfural content can be measured through the chromogenic reaction between TBA and furfitral indirectly. The results show that the TBA solution can exclude the interference of BHT. The TBA can react with furfural, and a new absorption peak appears at 390 nm. The peak height is liner with furfural content. The TBA colorimetry is not only effective to detect the furfural content in the transformer oil but also can overcome the complex measuring-process and time-consuming defects which provides a new way for detection of furfural of high performance liquid chromatography （HPLC）, content in transformer oil.