6309-52-0Relevant academic research and scientific papers
Production of novel biodiesel from transesterification over KF-modified Ca-Al hydrotalcite catalyst
Chen, Juan,Jia, Lihua,Guo, Xiangfeng,Xiang, Lijun,Lou, Shengfeng
, p. 60025 - 60033 (2014)
A series of KF-modified Ca-Al hydrotalcite (x KF/HTL-M) solid base catalysts was prepared in methanol, and characterized by thermogravimetry analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and carbon dioxide temperature-programmed desorption (CO2-TPD). The catalytic activity was investigated in the transesterification of ethylene glycol monomethyl ether (EGME) with methyl laurate (ML) to produce a novel biodiesel of ethylene glycol monomethyl ether monolaurate (EGMEML). The effect of the mass content of KF and the main reaction parameters such as EGME to ML molar ratio, amount of catalyst, reaction time and temperature on the yield of EGMEML were examined. The results indicate that a new phase of KCaF3 formed in xKF/HTL-M, and acted as the main active sites for the transesterification. In addition, xKF/HTL-M has excellent catalytic performance in the production of EGMEML. The highest yield of 97.7% was obtained over 24.7KF/HTL-M at EGME/ML molar ratio of 3.0, catalyst amount of 5 wt%, and reaction time of 4 h at 120°C. Moreover, the catalyst displays a good stability and reutilization. A satisfactory yield of 90% was obtained after use for five consecutive cycles without significant deactivation. Finally, the activation energy (Ea) of the reaction of EGME with ML over 24.7KF/HTL-M was obtained as 27.11 kJ mol-1.
Synthesis of ethylene glycol monomethyl ether monolaurate catalysed by KF/NaAlO2 as a novel and efficient solid base
Lou, Shengfeng,Jia, Lihua,Guo, Xiangfeng,Wu, Wenwang,Gao, Lianbing,Wu, Hongyuan,Wang, Jianjun
, p. 6921 - 6931 (2016/07/13)
A novel solid base catalyst of NaAlO2 modified with KF (x-KF/NaAlO2) was prepared using a wet-impregnation method and used for the synthesis of ethylene glycol monomethyl ether monolaurate (EGMEML) via transesterification of ethylene glycol monomethyl ether (EGME) and methyl laurate (ML). The catalyst was characterized using the Hammett indicator method, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy with an energy dispersive spectrometer. The effect of the reaction parameters such as the amount of KF loading, molar ratio of EGME to ML, dosage of the catalyst, reaction time and temperature on the yield of EGMEML was investigated. These characterizations led to a conclusion that the reaction between NaAlO2 and KF mainly generates fluoroaluminates, which act as the main active sites for the transesterification. The catalyst shows excellent catalytic activity and good stability. The highest yield of 91% was obtained over 30%-KF/NaAlO2 at an EGME/ML molar ratio of 3.0, a catalyst amount of 5 wt%, and a reaction time of 4 h at 120 °C. A yield of 80% was obtained after use for three consecutive rounds without reactivation. Furthermore, a desirable yield of 88.0% of a novel biodiesel of ethylene glycol methyl ether soybean oil monoester was obtained with 30%-KF/NaAlO2 as a catalyst. Moreover, it was found that the reaction follows second-order kinetics, the activation energy (Ea) of the reaction of EGME with ML equals 56.54 kJ mol-1, and the thermodynamic parameters of activation were evaluated based on an activation complex theory of the reaction, and the following data were obtained: ΔG? > 0, ΔH? > 0 and ΔS? 0, indicating the unspontaneous and endergonic nature of the reaction of EGME with ML. A Koros-Nowak test was conducted and the results confirmed that the diffusion limitations did not affect the catalytic activity. Finally, a few of the physicochemical properties of the EGMEML as biodiesel were determined, and the values were within those of European standards.
