Electrochemical Behavior of the Antioxidant 2,6-Di-tert-butyl-4-methylphenol in an Electrolyte Containing Transformer Oils

Aging of transformer oils could shorten the life of a transformer. Electrochemical behavior of the antioxidant 2,6-di-tert-butyl-4-methylphenol (BHT) in an electrolyte containing transformer oils was investigated. Cyclic voltammograms were obtained from electrochemical tests under different temperatures, and the quasi-reversible behavior for BHT on glassy carbon electrode was confirmed by the characteristics of the peak currents. The diffusion coefficients of BHT under different temperatures were evaluated from the dependence of the peak current density on the potential scan rates in the cyclic voltammograms, and it was found that the diffusion coefficient increases with increasing temperature. Diffusion activation energy of BHT was also calculated to be 29.29 kJ mol(-1), according to the relationship between the diffusion coefficient and temperature. Determination of the antioxidant content in transformer oils by electrochemical techniques and appropriate addition of the antioxidant, which can effectively avoid the transformer insulation fault caused by the aging of oils, prolong the service life of transformer oils and reduce the discharge of waste transformer oils.