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Vegetable oils and their derivatives are of great interest because of their abundance and renewability. This paper prepares nonanal (N) and methyl 9‐oxonanoate (M) from methyl epoxystearate (ME) with WO3∙0.33H2O, WO3∙H2O, and WO3∙2H2O as catalysts and H2O2 as the oxidant without the use of organic solvent. The reaction temperature, catalyst amount, H2O2 amount, and reaction time effects on ME conversion and N/M yield are investigated. The results show that WO3∙H2O has the best catalytic performance. The optimal reaction conditions are: reaction temperature 60 °C, reaction time 40 min, ME/H2O2/WO3∙H2O molar ratio 1/1.2/0.4, under which the ME conversion and N/M yield reach 95% and 70%, respectively. WO3∙nH2O reacts with H2O2 to form soluble tungsten anions, resulting in severe tungsten loss. Al‐MCM‐41 materials with different silicon to aluminum molar ratios are added to the reaction system as adsorbents to recover the catalyst by effective adsorption of tungsten anions. The adsorption performance improves as the Si/Al ratio decreases, however, the ME conversion and N/M yield decrease. Thus, 50 is the most suitable Si/Al ratio. The ME conversion and N/M yield can still reach 90% and 60% after four times of use. Practical applications: The nonanal has a natural fragrance and can be used in the cosmetic industry as well as in the preparation of bio‐based surfactants. The methyl 9‐oxonanoate can be converted into polymer monomers by hydrogenation or amination. The results show that WO3∙nH2O has good catalytic activity, and a satisfying yield of aldehyde products is obtained under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The hydrodynamic cavitation multiphase reactor (HCMR) is emerging as a promising alternative for the intensification of liquid–liquid heterogeneous reactions, but research on HCMR modeling is lacking. In this article, an HCMR model was developed using Prileschajew epoxidation as the model system. First, based on experimental measurements of oil/water two‐phase flow downstream of hydrodynamic cavitation devices, semiempirical correlations were proposed to describe the droplet size and droplet size distribution (DSD) as functions of flow conditions and geometry parameters. Then, with boundary conditions calculated by the DSD correlation, a droplet dynamics simulation in a reaction tank was performed by computational fluid dynamics coupled with population balance model to obtain the two‐phase interfacial area. Finally, the acquired reactor model was substituted into an overall kinetic model, to simulate the epoxidation reaction in HCMR. Model predictions were verified by experimental results measured on an industrial scale HCMR. [ABSTRACT FROM AUTHOR]

Epoxidized oils are eco‐friendly plasticizers, which are industrially produced through the epoxidation reaction in a formic acid‐hydrogen peroxide autocatalyzed system. The fundamental knowledge to describe the phase equilibrium of systems after epoxidation reaction is lacking, which is crucial for the design of the purification facilities. This work reported experimental data for the liquid–liquid equilibrium of three systems, i.e., epoxidized fatty acid methyl esters + formic acid + water, epoxidized fatty acid 2‐ethylhexyl esters + formic acid + water, and epoxidized soybean oil + formic acid + water, in the temperature range (303.15–348.15) K under atmospheric pressure. The results indicated that the liquid–liquid equilibrium constant of formic acid in the systems followed the order of epoxidized fatty acid 2‐ethylhexyl esters > epoxidized fatty acid methyl esters > epoxidized soybean oil. Moreover, the obtained experimental data were correlated using nonrandom two liquid (NRTL) and universal quasi chemical (UNIQUAC) models. The maximum root mean square deviation (RMSD) values as low as 0.0052 and 0.0263 were estimated using the NRTL and UNIQUAC model, respectively. The NRTL model is more suitable than the UNIQUAC model to describe the liquid–liquid equilibrium behavior of these ternary systems. [ABSTRACT FROM AUTHOR]

At present, the utilization of grease has attracted more and more attention. This article presents a simple method that efficiently cleaves methyl oleate‐derived methyl 9,10‐epoxystearate (a) to give high yields of methyl 9‐oxononanoate (d) with nonanal (c) as co‐product. A WO3/MCM‐41 catalyst is prepared via direct mixed‐gel synthesis. The catalyst is tested in the oxidative cleavage of a to produce d which can be used as a polymer precursor or an important feedstock. The effects of WO3 loading, temperature, time, H2O2/a molar ratio, catalyst/a weight ratio, and t‐BuOH/a weight ratio on the a conversion and d yield are examined using single‐factor experiments. The optimal reaction conditions are determined by orthogonal experiments. The optimal WO3 loading, temperature, time, H2O2/a molar ratio, catalyst/a weight ratio, and t‐BuOH/a weight ratio are 35%, 80 °C, 20 min, 1.3, 0.04, and 0.5, respectively. Under these conditions, the a conversion and d yield reach 99.4 and 78.4%, respectively. In addition, the catalyst shows no significant decrease in activity after being reused three times. Moreover, the reaction mechanism is studied based on the product distribution over time. Practical Applications: Few studies on methyl 9,10‐epoxystearate used as the raw material to give methyl 9‐oxononanoate and nonanal are found. Because the ethylene oxide bond is more unstable than the carbon–carbon double bond, the oxidative cleavage of methyl 9,10‐epoxystearate is easier than cleavage of methyl oleate that allows the oxidative cleavage to be done under milder conditions. Methyl 9‐oxononanoate can be converted to a monomer of high‐value polymers and is also an important feedstock in the production of chemicals. The co‐product nonanal is a natural spice which can be used in the fragrance industry. The results show that the reaction time is short and methyl 9‐oxononanoate yield is high under mild reaction conditions. The method in this study can also be widely used in other oxidative cleavage reactions of epoxides. Methyl 9,10‐epoxystearate is used as the raw material to produce methyl 9‐oxononanoate with nonanal as co‐product using WO3/MCM‐41 as catalyst and H2O2 as oxidant. [ABSTRACT FROM AUTHOR]

Abstract: Owing to the decrease of global oil price, development of downstream value‐added products is important to biodiesel industry. In this study, we used palmitic acid methyl ester (PAME) as a starting material to produce 2‐ethylhexyl palmitate (2‐EHP), an environmentally friendly biolubricant product, which was derived from the transesterification of fatty acid methyl esters and long chain fatty alcohols. Conventional synthetic routes of 2‐EHP have disadvantages, including high catalyst price, low conversion efficiency, and pollution issues. To solve these problems, in situ transesterification of PAME with 2‐ethylhexanol (2‐EH) was conducted over unsupported potassium carbonate as heterogeneous catalyst. The optimal reaction temperature, 2‐EH to PAME molar ratio, and catalyst to PAME mass ratio were 180 °C, 3:1, and 3.0 wt%, respectively. The PAME conversion reached up to 100% within 1 hour under the optimal conditions. In addition, a kinetic model describing the experimental data over a temperature range of 160–180 °C was developed. The dependence of kinetic rate constant (k) on temperature was evaluated, and the activation energy (Ea) for the transesterification of PAME with 2‐EH was calculated to be 57.04 kJ mol−1. [ABSTRACT FROM AUTHOR]

In this study, the mass transfer and reaction kinetics of soybean oil epoxidation using concentrated hydrogen peroxide in a formic acid-autocatalyzed reaction system were studied in detail. Studying the mass transfer of formic acid showed that the influence of reactant diffusion near the interface is eliminated when the stirring rate is > 120 rpm in a double-stirred cell, and the mass transfer rate decreases greatly with the conversion of double bonds and a decrease of reaction temperature. A temperature increase has little impact on the equilibrium of formic acid in the oil/water system, while an increase of epoxidized soybean oil significantly increases the value of the partition coefficient of formic acid. Another important aspect in the kinetic study is the decomposition of performic acid, which can cause the reduction of H2O2 and formic acid during the reaction. Finally, a biphasic model, which considers all reactions in oil and aqueous phases, the equilibrium and mass transfer of reagents and products between the phases, and the evolution of proton concentrations with time, was developed to describe the epoxidation process. [ABSTRACT FROM AUTHOR]

This work described a general strategy to enhance a typical organic-aqueous heterogeneous green oxidation reaction by introducing surface tunable magnetic nanoparticles into liquids to form a controllable Pickering emulsion. We synthesized cross-linked polystyrene (PS)-covered Fe3O4 nanoparticles grafted with different N-alkyl imidazoles and systematically discussed the effect of surface properties on the formation of emulsions. By loading such particles, the dichloromethane-water-based 2,2,6,6-tetramethylpiperidine-1-oxyl-mediated Montanari oxidation system was converted from the unstable millimeter-scale dispersion into a stable micrometer-scale emulsion, which significantly reduced the reactant transfer distance and resulted in a significantly high overall reaction rate. This reaction efficiency is elucidated in terms of unique properties inherent in an emulsion, including the self-assembly of Fe3O4/PS and Fe3O4/PS[im-C n]Cl ( n=1, 4, 6, and 10) nanoparticles, well ensuring a large specific surface area of the water-oil interface. [ABSTRACT FROM AUTHOR]

This study demonstrated the use of a magnetic superhydrophobic polymer nanosphere cage derived from a Pickering emulsion as a framework for miceller catalysis in biphasic media. We designed this system through the covalent stabilisation of active site (2,2,6,6-tetramethylpiperidine 1-oxyl)-grafted amphiphiles onto the magnetic hydrophobic core to form a micelle-like architecture and used it as a Pickering emulsifier to develop a new kind of micelle-catalysed biphasic system. The catalysis results reveal that these fixed micelle-tethered 2,2,6,6-tetramethylpiperidine 1-oxyl catalysts demonstrate much higher activity than their soluble counterparts in the biphasic Montanari oxidation of alcohols, which could be due to the unique properties of Pickering emulsion and miceller catalysis. In addition, the excellent magnetic response ensures the efficient recycling of the catalyst by magnetic decantation. The catalyst can be recycled at least 10 times without significant loss of activity or degradation of magnetic susceptibility. Moreover, this study demonstrates that this new Pickering emulsion-based and micelle-catalysed biphasic system is technically simple and practically applicable. [ABSTRACT FROM AUTHOR]

The cover picture shows a general strategy to improve the reaction of a typical organic–aqueous heterogeneous green oxidation system, in which surface properties and tunable magnetic nanoparticles were introduced to form a controllable and well‐dispersed emulsion. In their Full Paper, L. Feng et al. reveal that the addition of nanoparticles with proper surface modification can result in improved Montanari reactions compared with the conventional reaction system. The article highlighted by this cover can be found on p. 616 ff. of Issue 4, 2015. [ABSTRACT FROM AUTHOR]