Abstract
Epoxidation of high-linolenic perilla oil was carried out in the presence of solid acidic ion-exchange resin at varying reaction temperatures for 8 h. A pseudo two-phase kinetic model that captures the differences in reactivity of double bonds at various positions in the fatty acid of a triglyceride molecule during both epoxy formation and cleavage was developed. The proposed model is based on the Langmuir-Hinshelwood-Hougen-Watson (L-H-H-W) postulates and considers the adsorption of formic acid on the catalyst as the rate-determining step. To estimate the kinetic rate constants of various reactions, genetic algorithm was used to fit experimentally obtained iodine and epoxy values of epoxidized perilla oil. A re-parametrized form of Arrhenius equation was used in the proposed model to facilitate the precise estimation of parameters with least computational effort. The obtainment of the least error between experimentally determined and theoretically predicted iodine and epoxy values indicates the robustness of the proposed model.
Highlights
In this regard, epoxidation of triglycerides via Prilezhaev reaction has been widely studied in the presence of inorganic acid as catalyst, but is often critiqued for the role of the acid in causing extensive oxirane cleavage during the reaction[7]
All these models have focused only on high-oleic (C18:1) vegetable oils, thereby ignoring the effect of glycerol center on the reactivity of double bonds present in different positions in the fatty acids of a triglyceride molecule[5,18]. This becomes critical, given that Janković et al.[18] have reported that a modified version of P-H model which accounts for fatty acid composition is more accurate in predicting epoxidation kinetics of soybean oil containing 10% linolenic acid (C18:3)
This paper details a P2P model that considers variation in reactivity of double bond due to the effect of glycerol center based on its position during the epoxidation reaction accounting for both epoxy formation and cleavage
Summary
Epoxidation of triglycerides via Prilezhaev reaction has been widely studied in the presence of inorganic acid as catalyst, but is often critiqued for the role of the acid in causing extensive oxirane cleavage during the reaction[7]. AIER possesses the ability to trap various reactants that can react with epoxy, such as formic acid and hydrogen peroxide, resulting in EVOs with minimal oxirane cleavage[8,9,10] Such a shift is marked by enhanced complexity in epoxidation reaction kinetics due to chemical reactions occurring in three phases (oil, water and solid catalyst)[11]. The P2P model is observed as being better in predicting epoxidation kinetics of heterogeneously catalyzed reactions when compared with the P-H model[6] All these models have focused only on high-oleic (C18:1) vegetable oils (i.e., containing double bond only at the 9th position), thereby ignoring the effect of glycerol center on the reactivity of double bonds present in different positions in the fatty acids of a triglyceride molecule[5,18]. The outcome of this work can enable the selection of optimal synthesis conditions for triglycerides with high unsaturation content that will result in EVOs superior to conventional DGEBA for futuristic applications
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
