Fig. 17: FTIR spectrum of IGKO.
Conclusion
In this work, it has been established that process parameters
(temperature, time and particles size), influenced the IGK oil yield.
This is due to the fact that increases in temperature and time resulted
in the increase in the IGK oil yield, while smaller particle size gave
higher IGK oil yield. The highest oil yield of 68.80 % was obtained at
55 °C, 150 min., and 0.5 mm particle size. The physicochemical
properties of the IGK oil indicated its potential for use as transformer
fluid upon further treatment. Of the two kinetic models studied, pseudo
second order gave better fitting to the experimental data than
hyperbolic model. The activation energies determined using Arrhenius
equation and modified form of Arrhenius equation for pseudo second order
and hyperbolic models, respectively, were all positive, an indication
that oil extraction from IGK is an endothermic process. The obtained
results indicate that irrespective of the model used, the rate constant
k and the constant related to maximum extraction yield
C2, for pseudo second order and hyperbolic models,
respectively were temperature dependent, as they increased with
temperature increase. Also, the constants k and C2 for
pseudo second order and hyperbolic models respectively were more
temperature sensitive for larger particles size than for the smaller
ones. This is manifested in the higher values of the activation energies
obtained for larger average particles sizes. Kinetic models equations
were successfully developed to describe the IGK oil extraction processes
under the different process parameters (temperature, time and particle
size) for both models. Finally, the ∆G, ∆S and ∆H values obtained at the
different particles sizes during the extraction indicated that the
process was spontaneous, irreversible and endothermic.