Resumo

DELGADO-ARROYO, F; LEON-SILVA, U; SALDIVAR-GUERRERO, R.  e  HUACUZ-VILLAMAR, J.M. Moisture removal in mineral insulating oils by a resinous residue of Opuntia ficus-indica. RIIIT. Rev. int. investig. innov. tecnol. [online]. 2018, vol.6, n.33. ISSN 2007-9753.

The feasibility of application of a resinous residue (RR) found in Opuntia ficus-indica leaves for the elimination of moisture in mineral insulating oils was investigated. The RR was characterized physicochemically by infrared Fourier transform spectroscopy (FT-IR), thermogravimetric analysis (TGA) and solubility and absorption tests. In addition, the mineral insulating oil used in this work was characterized by a Karl Fischer titration and dielectric strength tests. The results of FT-IR indicated the presence of functional groups of type O-H, C=O and C-H mainly. The RR was insoluble in various organic solvents and distilled water. According to the TGA results, the RR sample contains approximately 9 % moisture, 73 % organic components and approximately 18 % residual components. The RR showed a high absorption capacity and moisture retention. The mineral oil increased its dielectric strength after the drying process. The RR of Opuntia ficus-indica is feasible for its application in the removal of moisture (on-line) in the mineral oil of electric transformers.

Palavras-chave : Absorption; dielectric strength; FT-IR spectroscopy; Karl Fischer; thermogravimetric analysis.