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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.

Oxidized starch is important for paper coating because of its good mechanical and sizing properties. Traditionally, starch oxidation is performed by different heavy metals as catalysts and chlorites or chlorines as oxidizing agents. In this study, an environmentally friendly method was developed, utilizing iron tetrasulfophthalocyanine as a catalyst only in small amounts and hydrogen peroxide as a clean oxidant. It has been previously shown that the method works well, but analysis of the kinetic data as well as catalyst deactivation was difficult because of the semibatch operation mode. In this study, hydrogen peroxide was employed in a batch mode, allowing more simple analysis methods for determining the degree of substitution, starch degradation, and hydrogen peroxide decomposition kinetics. Additionally, the effect of adding the catalyst continuously into the solution, as well as the influence of ultrasound treatment on starch prior to oxidation, was studied. The batch-mode results showed DS COOH ) 0.73 for 100 anhydroglucose units at 52°Cand pH 10, whereas adding the catalyst continuously increased DS COOH to 1.62. An increased DS COOH was obtained with the ultrasound-treated starch, which shows that ultrasound is a promising method for enhancing the reaction performance.