KINETIC AND THERMODYNAMIC EVALUATION OF THE EPOXIDATION OF ALLANBLACKIA FLORIBUNDA SEED OIL FOR INDUSTRIAL APPLICABILITY

Abstract

Epoxidation of seeds oils has attracted research concerns due to its industrial significance. Allanblackia floribunda seed oil (ASO) was subjected to epoxidation at different temperatures with a view to
establishing its kinetics and thermodynamic properties for possible industrial applications. The seed oil was extracted and characterized for its physicochemical properties using conventional methods. The percentage oil content, peroxide value, iodine value, acid value and saponification value were found as 63%, 4.55 meq/kg, 34.9 gI2/100g, 0.64 mg KOH/g and 201.8 mg KOH/g respectively. Oil was found as non-drying with fatty acid content of high molecular weight. Oils with such characteristics are known to be stable against rancidity and possible oxidation. Oxirane analysis gave data which shows the rate of epoxidation dependence on temperature and time. This satisfies the possibility of epoxidizing ASO oil
and confirms the formation of epoxidized oil from its seed. Pseudo-zero order kinetics with respect to oxirane formation was found from the epoxidation kinetics. Their rate constants were seen as 0.025 hr-1, 0.028 hr-1 and 0.04 hr-1 at 50 0C, 60 0C and 70 0C respectively. Ea, ∆H≠, ∆S≠ and ΔG≠ were found as 33.73kJmol-1, 17.04kJmol-1, -0.224kJmol-1 K-1 and 91.632 kJmol-1 respectively. Thermodynamic evaluation shows that the epoxidation process was kinetically favorable, but thermodynamically
unfavorable for enthalpy, entropy and Gibb’s energy; as such the process is not spontaneous at the temperatures studied. The result herein presents substantial reference data on the modification of ASO for diverse applicability and constitutes valuable literature database on the epoxidation of ASO for industrial applications