Yujiao Zhang,Shengli Niu,Sunwen Xia,Sitong Liu,Jisen Liu
The novel heterogeneous catalysts of SrZr 1- x Fe x O 3 ( x = 0, 0.05, 0.10, 0.15, 0.20, 0.25, 0.30 or 0.40) with acid-base bifunctional property are prepared through the sol-gel method and applied in catalyzing transesterification and esterification from acidified oil to produce biodiesel . The substitution of Zr by Fe in the SrZrO 3 perovskite results in the lattice distortion to generate abundant surface oxygen vacancies . Also, the enhancement of electron density on active sites improves the acidity and basicity of catalyst to construct the acid-base pair sites for high efficiency of biodiesel production . The SrZr 0.75 Fe 0.25 O 3 catalyst shows the strongest catalytic activity and the maximum FAME yield of 99.5% is achieved at the reaction temperature of 178 °C, catalyst amount of 4.5 wt%, methanol to oil molar ratio of 19:1 and reaction duration of 3.4 h through optimizing reaction parameters by convolutional neural network . The catalyst exhibits strong acid resistance and the FAME yield of 93.9% is achieved with 30 wt% oleic acid addition, where methanol is readily adsorbed to Sr site for transesterification and free fatty acids are readily adsorbed to Fe site for esterification. In addition, the SrZr 0.75 Fe 0.25 O 3 catalyst shows satisfactory reusability and the FAME yield of 96.2% is maintained for the fifth reused cycle.
Soap stocks are by-products obtained during the refining process of vegetable oil, and are mainly feedstocks to produce acidified oil. In this work, an efficient process was developed to convert soap stock into a high-quality biofuel with low impurity content. A combination of acidification and catalytic cracking reactions employed as pretreatment was investigated to decrease the impurity content in the soap stock feedstock for obtaining a value-added biofuel. A high olefin content (approximately 47%) pyrolytic oil was obtained during the pretreatment. For further improvement of the cold flow properties, hydro-isomerization of pyrolytic oil for the formation of iso-alkanes over the Ce–Pt/SAPO-11and Ce–Pt/ZSM-5 catalysts was then carried out. The isomerization reaction temperature could be decreased to 320 °C because of the approximately 47% olefin content. The cold filter plugging point (CFPP) of the resulting product could be obtained at −11 °C, and the sulfur content could be decreased to lower than 10 ppm, which could meet the EN and ASTM specifications.
危险品化学品经营许可证（带存储）