RESUMO
Epoxidation-esterification of fatty acid methyl ester obtained from Irvingia gabonensis kernel oil (IGKO), as well as its characterization, kinetics and thermodynamics were the main focus of this study. The methyl ester obtained via base catalyzed transesterification was used for epoxidation-esterification modification process. Epoxidation kinetics and thermodynamics parameters were also investigated. The properties of the IGKO and epoxidized-esterified Irvingia gabonensis kernel oil (IGKO) methyl ester (MIGKOe) were determined using standard methods. Rate constant K and activation energy Ea for the epoxidation process was found to be of the order 10 - 5 Lmol-1s-1 and 46.02 kJ/mol, respectively. ΔG, ΔH, and ΔS values for the epoxidation process were (94.74-101.42 kJ mol-1), 43.30 kJ mol-1, and - 167.20 J mol-1 K-1, respectively, indicating the non-spontaneous, endothermic, and endergonic nature of the process. The physicochemical characteristics of MIGKOe were: 9 °C, 298 °C, 840 kg/dm3, 13.84 mm2/s, 1.351 mg KOH/g oil, 1.01 mg/kg and 39.78 kV, for pour point, flash point, density, viscosity, acid value, moisture content and dielectric strength, respectively. The MIGKOe properties indicated its potential for use as a bio-transformer fluid, upon further treatment with pour point depressant.
