Fig. 12: FTIR spectrum of PKO biolubricant obtained by epoxidation-esterification of methyl ester sample
3.5. Fatty Acid composition of PKO, and synthesized biolubricant
The fatty acid compositions of palm kernel oil (PKO), PKO biolubricant synthesized by transesterification with trimethylolpropane (TMP) (PKBLT), and PKO biolubricant synthesized by epoxidation-esterification (PKBLE) methods are presented in Table 2. Similarly, the fatty acid profile of PKO, PKBLT, and PKBLE are presented in Figs. 13, 14 and 15, respectively. From the results in the table, it could be seen that the saturated and unsaturated fatty acid compositions of PKO, PKBLT and PKBLE, were (72.69 % and 27.31 %), (81.81 % and 18.19 %), and (83.45 % and 16.55 %), respectively. This is an indication that the PKO, PKBLTand PKBLE samples were all highly saturated. For the PKO sample, the predominant saturated fatty acid was lauric acid, with 41.85 %. On the other hand, oleic acid was the predominant unsaturated fatty acid, with 17.45 %. Similar fatty acid composition was obtained for PKO by Alamu et al. [48]. However, there is the need to further improve on the saturated level of the PKO using modification prior to their possible application as biolubricant [4].
Table 2: Fatty acid compositions of the PKO, PKBLT and PKBLE samples