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Natural epoxy fatty acids such as Coronaric acid (9,10-epoxy-12Z-octadecenoic acid) and vernolic acid (12,13-epoxy-9Z-octadecenoic acid) are rich in of Vernolia galamensis, Vernolia anthelmintica and Chrysanthemums coronanium. The two fatty acids each contains an oxirana ring and a double bond C = C. The oil or its derivatives are suitable for industrial usage as reactive diffluent of alkyd resins, plasticizers and stabilizers, surface coatings, surfactants and lubricants, as intermediates in chemical reactions for making linear epoxides of composite materials and polymers. However, the use of such oils on an industrial scale is impossible due to limited resources. Therefore, epoxidation reactions need to be carried out to overcome the demand for partial epoxide fatty acids. Partially epoxidation of methyl linoleate at room temperature (30°C) in the presence of pyridine, methyltrioxorhenium (MTO) as catalyst and urea-hydrogen peroxide (UHP) as oxidant was studied by using response surface methodology (RSM). A five-level-four-factors central composite rotatable design (CCRD) was used to optimize the partially epoxidation conditions and study the effect of MTO, UHP, pyridine and reaction time on relative conversion to oxirane (RCO). Quadratic polynomial model was employed to generate response surface plots for RCO. At optimal condition, 79.05% monoepoxide was formed at the RCO of 58.15% under condition of 0.75 mol% mole ratio of MTO, 300 mol% mole ratio of UHP and 9 mol% of pyridine at 120 min reaction time. It can be concluded that the effect of UHP mole ratios was the dominant factor to control the degree of partial epoxidation of methyl linoleate followed by mole ratio of MTO, reaction time and mole ratio of pyridine to formed methyl 12,13-epoxy-9Z-octadecenoate or/and methyl 9,10-epoxy-12Z-octadecenoate.
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