Abstract The use of watermelon seed oil as feedstock for oleochemicals was studied. Oil was extracted from the seeds which was homopolymerized using HClO4 as catalyst. The homopolymer was used to prepare a variety of oleochemicals namely amine, amide, epoxide and copolymerized Phenol-Citrullus-lanatus polymer (CPCLP). Iodine value was determined for the oil, homopolymer (CLH) and the CPCLP as a measure of unsaturation. Viscometry studies were carried out to determine the molecular weights of products. FTIR and proton NMR were used to determine the structure of the oleochemicals. 13C NMR was used to further characterize the CPCLP.
The percentage oil yield is 56.86%. The iodine values were respectively 196.13g/100g, 127.96g/100g and 123.3g/100g for Citrullus-lanatus oil (CLO), homopolymer (CLH) and CPCLP. The molecular weights (x 107) of the oleochemicals were 510.8g/mol, 536.8g/mol, 543.8g/mol, 410.3g/mol, 566.8g/mol, and 759.0g/mol respectively for CLO, Citrullus-lanatus amide (CLAmide), Citrullus-lanatus amine (CLAmine), CLH, Epoxidized citrullus-lanatus polymer (ECLP) and CPCLP. FTIR spectra showed absorptions at (1720-1740) cm-1 of carbonyl group. The major peaks found in the proton NMR spectrum are vinyl protons (C=C-H) at (4.5-5.5) ppm, αΎ³-carbonyl protons and allylic protons at (2-3 and 1.8) ppm. CLAmine shows N-H peaks at 4.444 ppm and 4.490 ppm while CLAmide showed the CONHR peak at 5.775 ppm and 5.621 ppm respectively. CPCLP showed aromatic protons between 6.6ppm and 7.1ppm. The 13C NMR also confirm CPCLP structure.
The results showed that watermelon oil can be used to prepare useful oleochemicals that are of great importance to the economy with little or no environmental impairment.
Keyword: Oleochemical, Watermelon, Green chemistry, Feedstock, Environment.