Determination of antioxidants in vegetable insulating oils by HPLC

作者:Fang, Yuan; Luo, Yunbai*; Yu, Ping
来源:Journal of Renewable and Sustainable Energy, 2016, 8(3): 033103.
DOI:10.1063/1.4954235

摘要

Vegetable insulating oils (VIOs) have attracted wide attention for their high flash point, high insulation performance and degradability. However, the unsaturated fatty acids contained in VIOs reduce their oxidation stability, which requires the addition of some antioxidants to ensure their usage. Here, we establish a high-performance liquid chromatography (HPLC) method for determination of antioxidants in VIOs. The standard calibration curves of 3 analytes (PG, BHA, BHT) all show high linearity, and the correlation coefficients are all above 0.9994. Limits of detection of all three analytes range from 0.003 to 0.010 mg/ml; limits of quantitation range from 0.010 to 0.033 mg/ml. The new HPLC method is proved ideally suitable for the analysis of commercialized transformer oil Cooper-FR3 with precision (% RSD = 0.3%-0.7%) and accuracy (% recovery = 100.0%-102.1%), suggesting that this method is an efficient tool for routine screening of antioxidant contents in VIOs. We used this method to monitor the changes of antioxidant contents in the oxidation of two VIOs-soybean oil and rapeseed oil. Published by AIP Publishing.