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Production of epoxidized vegetable oils becomes more and more important because they are renewable, nontoxic, and biodegradable chemicals. At the industrial scale, the Prileschajew oxidation is used to produce epoxidized vegetable oils from the corresponding vegetable oils. This oxidation uses an oxygen carrier, which is a percarboxylic acid produced in situ in the aqueous phase, to epoxidize the unsaturated groups on the vegetable oils. One of the main drawbacks of this method is the presence of side reactions: ring-opening reactions of the epoxide group. To minimize the ringopening reactions and to find the most suitable reactor configuration, it is essential to investigate deeply the different ring-opening reactions.For this work, epoxidation of cottonseed oil by peracetic acid in a batch reactor was studied. By developing a suitable modeling strategy, the kinetic constants for the ringopening reactions by water, hydrogen peroxide and acetic and peracetic acids were estimated. It was found that ring opening by acetic and peracetic acids was faster than by water and hydrogen peroxide. Based on this model, it was found that a semibatch reactor where hydrogen peroxide and sulfuric acid were added is the most suitable configuration. K E Y W O R D Sepoxidation, kinetic modeling, liquid-liquid reaction system, parameter estimation 726

Epoxidation of oleic acid and cottonseed oil was conducted in a semibatch reactor with in-situ-formed percarboxylic acid (peracetic acid or perpropionic acid), using hydrogen peroxide as an oxidizing agent and carboxylic acid (acetic acid or propionic acid) as oxygen carriers. Amberlite IR-120 was implemented as the catalyst. The system was comprised of a loop reactor, where the mixture was pumped through a single-mode cavity in which microwave irradiation was introduced. A heat exchanger was integrated into the system to replace microwave heating, to compare the results obtained via microwave heating versus conventional heating. The catalyst loading effect was studied, as well as the influence of microwave irradiation and the implementation of the SpinChem rotating bed reactor (RBR), in hopes of decreasing the influence of the internal mass transfer. The application of microwave irradiation results in an improvement of the reaction yield in the absence of a catalyst.

The epoxidized group, also known as the oxirane group, can be considered as one of the most crucial rings in chemistry. Due to the high ring strain and the polarization of the C–O bond in this three-membered ring, several reactions can be carried out. One can see such a functional group as a crucial intermediate in fuels, polymers, materials, fine chemistry, etc. Literature covering the topic of epoxidation, including the catalytic aspect, is vast. No review articles have been written on the catalytic synthesis of short size, intermediate and macro-molecules to the best of our knowledge. To fill this gap, this manuscript reviews the main catalytic findings for the production of ethylene and propylene oxides, epichlorohydrin and epoxidized vegetable oil. We have selected these three epoxidized molecules because they are the most studied and produced. The following catalytic systems will be considered: homogeneous, heterogeneous and enzymatic catalysis.

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