Kinetics of soybean oil epoxidation with peracetic acid formed in situ in the presence of an ion exchange resin: Pseudo-homogeneous model

Abstract

A kinetic model was proposed for the epoxidation of vegetable oils with peracetic acid formed in situ from acetic acid and hydrogen peroxide in the presence of an acidic ion exchange resin as a catalyst. The model is pseudo-homogeneous with respect to the catalyst. Besides the main reactions of peracetic acid and epoxy ring formation, the model takes into account the side reaction of epoxy ring opening with acetic acid. The partitioning of acetic acid and peracetic acid between the aqueous and organic phases and the change in the phases? volumes during the process were considered. The temperature dependency of the apparent reaction rate coefficients is described by a reparameterized Arrhenius equation. The constants in the proposed model were estimated by fitting the experimental data obtained for the epoxidations of soybean oil conducted under defined reaction conditions. The highest epoxy yield of 87.73% was obtained at 338 K when the mole ratio of oil unsaturation:acetic acid:hydrogen peroxide was 1:0.5:1.35 and when the amount of the catalyst Amberlite IR-120H was 4.04 wt.% of oil. Compared to the other reported pseudo-homogeneous models, the model proposed in this study better correlates the change of double bond and epoxy group contents during the epoxidation process. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III45022]

Screening of ion exchange resin catalysts for epoxidation of oleic acid under the influence of conventional and microwave heating

“…In general, these results are comparable with the ones presented in Table 1, for the experiments conducted at 50 ∘ C with jatrofa, canola and soybean oil as well as oleic acid. 14,16,19…”

Catalytic developments in the epoxidation of vegetable oils and the analysis methods of epoxidized products

“…To overcome the drawbacks of the former system, to minimize the unwanted side reactions, and to improve the high epoxy yield, acidic ion exchange resins are becoming the substitutes for inorganic acid catalysts. 33–40 The reaction mechanisms of epoxidation by inorganic acid and AIERs are the same, in which the catalysts speed up the perhydrolysis (peracid formation) that is the rate determining step of the reaction. 41 Similarly, phase transfer agents play the part of catalysts for the epoxidation of vegetable oils as a solvent-free system.…”

Epoxidation of Linseed Oil by Performic Acid Produced In Situ

“…The formation of percarboxylic acid occurs in situ, in semibatch reactors, through the Bronsted acid-catalyzed reaction between a carboxylic acid and hydrogen peroxide. The Bronsted acid can be homogeneous, such as sulfuric and phosphoric acid, or heterogeneous, such as ion exchange resins and zeolites. − …”