Green and efficient epoxidation of methyl oleate over hierarchical TS-1

The epoxidation of methyl oleate(MO)was conducted in the presence of aqueous H2O2 as the oxidant and hierarchical TS-1(HTS-1)as the catalyst;the catalyst was synthesized using polyquaternium-6 as the mesopore template.The effects of various parameters,i.e.,H2O2/C=C molar ratio,oxidant concentration,amount of the catalyst,reaction temperature,and time,were systematically studied.Furthermore,response surface methodology(RSM)was used to optimize the conditions to maximize the yield of epoxy MO and to evaluate the significance and interplay of the factors affecting the epoxy MO production.The H2O2/C=C molar ratio and catalyst amount were the determining factors for MO epoxidation,wherein the maximum yield of epoxy MO reached 94.9%over HTS-1 under the optimal conditions.

Pyrolysis Characteristics and Kinetics of Methyl Oleate Based on TG-FTIR Method

The thermal decomposition characteristics of methyl oleate were preliminarily investigated under nitrogen atmo-sphere by a thermogravimetric analyzer when the ester was heated at a heating rate of 10℃/min from room temperature to 600℃. Furthermore, the pyrolytic and kinetic characteristics of methyl oleate were intensively studied at different heating rates. The gaseous species obtained during thermal decomposition were also identiifed by the TG-FTIR coupling analysis. The results showed that the pyrolysis of methyl oleate proceeded in three stages, viz. the drying stage, the main pyrolysis stage and the residual pyrolysis stage. The initial decomposition temperature, the maximum weight loss temperature, the peak decomposition temperature and the rate of maximum weight loss of methyl oleate increased with the increasing heating rates. Gaseous CO, CO2 and H2O were the typical decomposition products from pyrolysis of methyl oleate. In addition, a kinetic model for thermal decomposition of methyl oleate was built up based on the experimental results using the Coats-Redfern integral method and the multiplelinear regression method. The activation energy, the preexponential factor, the reaction order and the kinetic equation for thermal decomposition of methyl oleate were obtained. Comparison of the experimental data with the calculated ones and analysis of statistical errors of pyrolysis ratios demonstrated that the kinetic model was reliable for studying the pyrolysis of methyl oleate. Finally, the kinetic compensation effect between the preexponential factors and the activation energy in the pyrolysis of methyl oleate was also conifrmed.

Modification of methyl oleate for silicon-based biological lubricating base oil

A new kind of silicon-based biological lubricating base oil with good viscosity-temperature behavior,viscosity index,thermostability,oxidation stability and wear resistance performance was synthesized as a derivative of methyl oleate.Trimethylsilylation reaction was introduced to further improve methyl oleate oxidation stability and lubricity after epoxidation and open-ring reactions.The order of effectiveness of acid binding agent was N,N-diisopropylethylamine(DIEA) > pyridine > diethylamine > triethylamine,and the effects of various parameters on the trimethylsilylation reaction as well as on the silicon-oxygen bond stability and reaction yield were studied.A maximum yield of 34.54%was achieved at hydroxyl/trimethyl chlorosilane/DIEA molar ratio of1:1.25:1,reaction temperature 40℃,reaction time 1.5 h.