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固体酸碱 1

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生物柴油 1

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超临界法 1

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Biodiesel production by the transesterification of cottonseed oil by solid acid catalysts

CHEN He, PENG Baoxiang, WANG Dezheng, WANG Jinfu

《化学科学与工程前沿（英文）》 2007年第1卷第1期页码 11-15 doi: 10.1007/s11705-007-0003-y

摘要： Methyl esters (biodiesel) were produced by the transesterification of cottonseed oil with methanol in the presence of solid acids as heterogeneous catalysts. The solid acids were prepared by mounting HSO on TiO · nHO and Zr(OH), respectively, followed by calcining at 823K. TiO-SO and ZrOSO showed high activity for the transesterification. The yield of methyl esters was over 90% under the conditions of 230°C, methanol/oil mole ratio of 12:1, reaction time 8 h and catalyst amount (catalyst/oil) of 2% (w). The solid acid catalysts showed more better adaptability than solid base catalysts when the oil has high acidity. IR spectral analysis of absorbed pyridine on the samples showed that there were Lewis and BrØnsted acid sites on the catalysts.

关键词： BrØnsted reaction presence cottonseed biodiesel

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Transesterification of soybean oil to biodiesel over kalsilite catalyst

Guang WEN, Zifeng YAN

《化学科学与工程前沿（英文）》 2011年第5卷第3期页码 325-329 doi: 10.1007/s11705-010-0574-x

摘要： The transesterification reaction of soybean oil with methanol over kalsilite-based heterogeneous catalysts was investigated. The kalsilite was synthesized from potassium silicate, potassium hydroxide, and aluminum nitrate aqueous solutions by controlling the pH value at 13. After calcination in air at 1200°C, a very porous kalsilite (KAlSiO ) was obtained with surface pores ranging from 0.2 to 1.0 μm. However, this kalsilite had relatively low catalytic activity for the transesterification reaction. A biodiesel yield of 54.4% and a kinematic viscosity of 7.06 cSt were obtained at a high reaction temperature of 180°C in a batch reactor. The catalytic activity of kalsilite was significantly enhanced by introducing a small amount of lithium nitrate in the impregnation method. A biodiesel yield of 100% and a kinematic viscosity of 3.84 cSt were achieved at a temperature of only 120°C over this lithium modified catalyst (2.3 wt-% Li). The test of this lithium modified catalyst in pellet form in a laboratory-scale fixed-bed reactor showed that it maintained a stable catalytic performance with a biodiesel yield of 100% over the first 90 min.

关键词： kalsilite heterogeneous catalyst transesterification biodiesel

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酯交换反应在制备生物柴油上的应用

张怀渊,宋元达

《中国工程科学》 2010年第12卷第1期页码 24-29

摘要：

生物柴油因其环境友好且可再生作为矿物柴油的替代燃料而备受关注，生物柴油主要通过均相酸碱催化、脂肪酶催化、超临界法和固体酸碱催化的酯交换反应制备得到，但各种制备方法各有优劣，均相酸碱催化法反应迅速，转化率高但存在后续处理复杂，污染严重等问题；脂肪酶催化法反应条件温和，对原料中的水和游离脂肪酸不敏感，不需要过量的甲醇参与反应，后续处理工序简单，但酶的成本过高，这是制约其商业化发展的最大阻碍；超临界法是制备生物柴油的新技术，反应迅速，不需要催化剂，油脂转化率非常高，但其反应需要高温高压且能耗很大；固体酸碱催化剂

关键词：生物柴油酯交换反应均相酸碱固体酸碱脂肪酶超临界法

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Application of heterogeneous catalysis to biodiesel synthesis using microalgae oil

《环境科学与工程前沿（英文）》 2021年第15卷第5期 doi: 10.1007/s11783-020-1343-9

摘要：

• Microalgae oil application for biodiesel synthesis is discussed.

关键词： Biodiesel Heterogeneous catalysis Transesterification Microalgae oil

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Metakaolinite as a catalyst for biodiesel production from waste cooking oil

Jorge RAMIREZ-ORTIZ, Merced MARTINEZ, Horacio FLORES

《化学科学与工程前沿（英文）》 2012年第6卷第4期页码 403-409 doi: 10.1007/s11705-012-1224-2

摘要： The use of metakaolinite as a catalyst in the transesterification reaction of waste cooking oil with methanol to obtain fatty acid methyl esters (biodiesel) was studied. Kaolinite was thermally activated by dehydroxylation to obtain the metakaolinite phase. Metakaolinite samples were characterized using X-ray diffraction, N adsorption-desorption, simultaneous thermo-gravimetric analyse/differential scanning calorimetry (TGA/DSC) experiments on the thermal decomposition of kaolinite and Fourier-transform infrared spectrometer (FTIR) analysis. Parameters related to the transesterification reaction, including temperature, time, the amount of catalyst and the molar ratio of waste cooking oil to methanol, were also investigated. The transesterification reaction produced biodiesel in a maximum yield of 95% under the following conditions: metakaolinite, 5 wt-% (relative to oil); molar ratio of oil to methanol, 1∶23; reaction temperature, 160°C; reaction time, 4 h. After eight consecutive reaction cycles, the metakaolinite can be recovered and reused after being washed and dried. The biodiesel thus obtained exhibited a viscosity of 5.4?mm ?s and a density of 900.1 kg?m . The results showed that metakaolinite is a prominent, inexpensive, reusable and thermally stable catalyst for the transesterification of waste cooking oil.

关键词： biodiesel metakaolinite transesterification waste cooking oil

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Rosin side chain type catalyst-free vitrimers with high cross-link density, mechanical strength, and thermal stability

《化学科学与工程前沿（英文）》 2023年第17卷第9期页码 1267-1279 doi: 10.1007/s11705-022-2291-7

摘要： The emergence of vitrimer, a new class of polymer materials can address the problem of recyclability, reprocess ability and recyclability of thermosetting plastics. Rosin, a natural product, is an ideal raw material for the preparation of polymers in a more sustainable way. Nevertheless, due to the huge steric hindrance caused by the hydrogenated phenanthrene ring structure, the cross-link density of materials is frequently lowered. In this study, hydrogenated rosin was adopted for preparing hydrogenated rosin side-chain type diacids, which were reacted with mixed epoxy to obtain rosin side-chain type vitrimers. It was completely characterized by differential scanning calorimetry test, thermogravimetric analysis, shape memory test and self-healing test. The prepared vitrimers exhibited good self-healing properties, excellent heat resistance (T_d = 352 °C) as well as high mechanical properties (tensile strength of 46.75 MPa). The tricyclic diterpene structure of rosin was introduced into the side chain in order to avoid the reduction of cross-link density resulting from the huge steric hindrance of the rigid tricyclic hydrophenylene skeleton. Vitrimers can undergo dynamic transesterification reaction without external catalysts due to the autocatalytic effect of tertiary amines from epoxy. Moreover, our work expanded the application field of rosin, increased the added value of rosin, and provided a novel method for preparing rosin-based vitrimers with ideal properties.

关键词： vitrimers rosin catalyst-free high mechanical properties dynamic transesterification reaction

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Ti incorporation in MCM-41 mesoporous molecular sieves using hydrothermal synthesis

Shengping WANG, Changqing MA, Yun SHI, Xinbin MA

《化学科学与工程前沿（英文）》 2014年第8卷第1期页码 95-103 doi: 10.1007/s11705-014-1405-2

摘要： Titanium-containing mesoporous materials (Ti-MCM-41) were obtained by hydrothermal synthesis. Such materials are active catalysts for the transesterification of dimethyl oxalate and phenol to produce diphenyl oxalate. To understand the role of the Ti in the catalytic process, Ti-MCM-41 samples with different Si/Ti ratios (from 5 to 100) were prepared and the samples were analyzed by Fourier transform infrared spectroscopy, UV-visible spectroscopy, and ammonia temperature programmed desorption. It was concluded that the Ti is incorporated into the framework of the MCM-41 and formed weak Lewis acid sites. In addition, the number of Ti(IV) sites increased as the amount of titanium increased. X-ray powder diffraction, N adsorption-desorption and transmission electron microscopy results showed that the Ti-MCM-41 samples have a hexagonal arrangement of mono-dimensional pores. A large number of Ti(IV) sites coupled with the mesoporous structure and large pore diameters are favorable for the transesterification catalytic properties of Ti-MCM-41.

关键词： Ti-MCM-41 mesoporous molecular sieve acid sites transesterification hydrothermal synthesis

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Challenge of biodiesel production from sewage sludge catalyzed by KOH, KOH/activated carbon, and KOH/CaO

Xuemin Wu,Fenfen Zhu,Juanjuan Qi,Luyao Zhao,Fawei Yan,Chenghui Li

《环境科学与工程前沿（英文）》 2017年第11卷第2期 doi: 10.1007/s11783-017-0913-y

摘要： The preparation reactions were catalyzed by base solid catalysts. The preparation reactions were catalyzed by two loaded catalysts and KOH. KOH/activated carbon was a better catalyst for biodiesel production. The considerable compounds content, abundance, and low costs involved has led to the proposal to use sewage sludge as raw material for biodiesel production. The transesterification reaction is catalyzed using an acid catalyst instead of base catalysts because of the high free fatty acid concentration. However, the use of a base catalyst, particularly a solid base catalyst, has certain advantages, including faster reaction speed and easier separation. In this study, we utilize in situ transesterification by base catalyst (KOH, KOH/activated carbon (AC) and KOH/CaO) with sewage sludge as raw material. Many conditions have been tested to increase biodiesel yield through single-factor tests, including mass fraction and catalyst dosage. Preliminary experiments have optimized reaction time and temperature. However, the three catalysts did not work better than H SO , which had a maximum yield of 4.6% (dry sewage sludge base) considering the purity by KOH, KOH/CaO, and KOH/AC. The features of the catalyst were analyzed using XRD, BET and SEM. As to BET of KOH/AC and the good spiculate formation of KOH crystal appears to be essential to its function. As for KOH/CaO, the formation of K O and absorption points is likely essential.

关键词： Biodiesel Sewage sludge Base catalyst In situ transesterification