v6n1doi10.4322/sc.2014.019 | Scientia Chromatographica

http://dx.doi.org/10.4322/sc.2014.019

Supercritical fluid extraction followed by gas chromatography-mass spectrometry determination of electrical-grade insulating oil residues from activated bauxite

Basseto, Armando; Lanças, Fernando M.

Palavras-chave: SFE, GC-MS, insulating oil, activated bauxite, remediation, CO2.

Resumo: The electrical-grade insulating oils widely used in high-voltage power equipment produce degradation by-products during their service life. Filtering the aged oil through an adsorbent material such as activated bauxite usually eliminates such by-products. As a consequence the adsorbent will be contaminated with several chemical species thus hindering its direct discharge in the environment. In the present work, a methodology was developed and optimized to extract oil residues adsorbed in activated bauxite by dynamic supercritical fluid extraction (DYN-SFE) employing CO2 as extraction solvent. Characterizing the extracted residues by GC-MS allowed following the remediation process, showing that the developed method was effective in extracting the vast majority of the compounds detected in the insulating oil studied. However, the extraction of carboxylic acids from oil degradation requires to be optimized in a future study.

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