Analysis of furfural in transformer oil using HPLC and UHPLC

Insulating paper is used in coil of electric transformer. Furfural is generated by deterioration of the paper. Measuring the amount of furfural allows to estimate the aged deterioration of electric transformer. So, this measurement is essential to maintain the product reliability.

In this application, measurements of furfural dissolved in transformer oil is performed with HPLC and UHPLC. Besides, two methods, solvent extraction method and solid-phase extraction method with silica gel, are applied as a pre-treatment method.