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2023 2

2016 1

2014 2

2013 1

2009 1

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Au/Ti双功能催化剂 1

H₂有效利用率 1

丙烯环氧化 1

多不饱和脂肪酸 1

多元醇 1

密度泛函理论 1

橡胶籽油 1

环氧化 1

配位不饱和Ti位点 1

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Controllable synthesis of a large TS-1 catalyst for clean epoxidation of a C=C double bond under mild

《化学科学与工程前沿（英文）》 2023年第17卷第6期页码 772-783 doi: 10.1007/s11705-022-2280-x

摘要： Development of a titanium silicalite-1 (TS-1) catalyst with good crystallinity and a four-coordinate Ti framework is critical for efficient catalytic oxidation reaction under mild conditions. Herein, a size-controlled TS-1 zeolite (TS-1#0.1ACh (acetylcholine)) was synthesized via steam-assisted crystallization by introducing acetylcholine as a crystal growth modifier in the preparation process, and TS-1#0.1ACh was also employed in epoxidations of different substrates containing C=C double bonds. The crystalline sizes of the as-synthesized TS-1#0.1ACh catalysts were controlled with the acetylcholine content, and characterization results showed that the particle sizes of highly crystalline TS-1#0.1ACh zeolite reached 3.0 μm with a good Ti framework. Throughout the synthetic process, the growth rate of the crystals was accelerated by electrostatic interactions between the connected hydroxyl groups of the acetylcholine modifier and the negatively charged skeleton of the pre-zeolites. Furthermore, the TS-1#0.1ACh catalyst demonstrated maximum catalytic activity, good selectivity and high stability during epoxidation of allyl chloride. Importantly, the TS-1#0.1ACh catalyst was also highly versatile and effective with different unsaturated substrates. These findings may provide novel, easily separable and large TS-1 catalysts for efficient and clean industrial epoxidations of C=C double bonds.

关键词： size-controlled TS-1 crystal modifier steam-assisted crystallization epoxidation

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Selective epoxidation of linear terminal olefins with metalloporphyrins under mild conditions

Xiaoguang BAI, Yuanbin SHE

《化学科学与工程前沿（英文）》 2009年第3卷第3期页码 310-313 doi: 10.1007/s11705-009-0168-7

摘要： The epoxidation of linear terminal olefins with metalloporphyrins in the presence of dioxygen and isobutyraldehyde under ambient temperature and atmospheric pressure was investigated. The results show that all olefins could be smoothly converted to epoxides with high selectivities (70%-90%). For the metalloporphyrins with different catalytic activities within 1-hexene epoxidation in the order of Fe>Mn>Co, T( -Cl)PPFe(Ⅲ)Cl was most effective, with a 41.7% yield and 80.2% selectivity of 1,2-epoxyhexane. Various amounts of catalyst were investigated, and it was found that with only 10 ppm catalyst the yield of 1,2-epoxyhexane and turnover number (TON) could reach up to 41.9% and 41859, respectively.

关键词： metalloporphyrins olefins dioxygen epoxidation

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橡胶籽油中多不饱和脂肪酸的分离及其环氧化反应研究

黄元波,杨晓琴,杨静,郑云武,郑志锋

《中国工程科学》 2014年第16卷第4期页码 74-78

摘要：

对橡胶籽油（rubber seed oil，RSO）中的多不饱和脂肪酸（polyunsaturated fatty acid，PUFA）进行了分离纯化，以此为原料，采用过氧乙酸原位法合成了环氧化多不饱和脂肪酸并进行了红外分析，探讨了30 %过氧化氢（H₂O₂）的用量、冰乙酸的用量、反应时间和反应温度对环氧化反应的影响。结果表明，当原料与30 % H₂O₂用量比为1∶2.5（质量比）、与冰乙酸的用量比为1∶0.9（质量比），在65 ℃下反应3 h，环氧化程度最高，产物环氧值可达8.28 mol/100 g，相对环氧转化率为82 %，双键转化率为97 %。

关键词：橡胶籽油多不饱和脂肪酸环氧化多元醇

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Effect of triethylamine treatment of titanium silicalite-1 on propylene epoxidation

Juan XU,Yaquan WANG,Wenping FENG,Yi LIN,Shuhai WANG

《化学科学与工程前沿（英文）》 2014年第8卷第4期页码 478-487 doi: 10.1007/s11705-014-1453-7

摘要： Titanium silicalite-1(TS-1) treated with triethylamine (TEA) solution under different conditions was characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectrum (FTIR), ultraviolet-visible diffuse reflectance spectrum (UV-Vis), nitrogen physical adsorption and desorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The characterization results show that many irregular hollows are generated in the TS-1 crystals due to the random dissolution of framework silicon and the volume of the hollow cavities increase with increasing the TEA concentration, and the treatment temperature and time. The modified TS-1 samples improved in varying degrees the catalyst life for the epoxidation of propylene in a fixed-bed reactor probably due to the generation of the hollows to make it easy for the reactants and products to diffuse out of the channels.

关键词： titanium silicalite-1 triethylamine hollow cavity epoxidation of propylene catalyst life

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Deactivation and regeneration of TS-1/SiO

Hainan SHI, Yaquan WANG, Guoqiang WU, Wenping FENG, Yi Lin, Teng ZHANG, Xing JIN, Shuhai WANG, Xiaoxue WU, Pengxu YAO

《化学科学与工程前沿（英文）》 2013年第7卷第2期页码 202-209 doi: 10.1007/s11705-013-1328-3

摘要： TS-1/SiO catalyst for the epoxidation of propylene with hydrogen peroxide in a fixed-bed reactor has been investigated. The catalyst activity decreases gradually with the online reaction time, but the selectivity of propylene epoxide is kept at about 93%. The fresh, deactivated and regenerated catalysts were characterized with X-ray diffraction, Fourier transform infrared spectroscopy, ultra-violet-visible diffuse reflectance, Brunner-Emmett-Teller method and thermogravimetric analysis, and the deactivated catalyst was regenerated with H O /methanol solution. Compared with the fresh catalyst, both the framework structure and the content of titanium in the framework of the deactivated and regenerated TS-1/SiO catalysts were not changed. The major reason of the catalyst deactivation was the blockage of the channels of the catalyst by bulky organic by-products, which covered the active centers of titanium in TS-1. The deposited materials on the deactivated TS-1/SiO catalyst could be removed by treatment with hydrogen peroxide/methanol solution or pure methanol; the higher the treatment temperature and the higher the concentration of H O in methanol, the higher the extent of the regeneration. The regeneration treatment did not influence the product selectivity in the propylene epoxidation.

关键词： TS-1/SiO₂ epoxidation of propylene fixed-bed reactor deactivation regeneration

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Synthesis of a cardanol-amine derivative using an ionic liquid catalyst

Atanu Biswas, Carlucio R. Alves, Maria T. S. Trevisan, Roseane L. E. da Silva, Roselayne F. Furtado, Zengshe Liu, H. N. Cheng

《化学科学与工程前沿（英文）》 2016年第10卷第3期页码 425-431 doi: 10.1007/s11705-016-1581-3

摘要： Cardanol is a biobased raw material derived from cashew nut shell liquid. In order to extend its utility, new derivatives and additional applications are useful. In this work cardanol was first epoxidized, and a novel aniline derivative prepared from it under mild reaction conditions with the help of an ionic liquid catalyst. The reaction chemistry was studied by using nuclear magnetic resonance. The resulting aminohydrin adduct showed antioxidant property and should also be a useful synthon for further reactions. As an example, the aminohydrin was shown to undergo a condensation reaction with formaldehyde to form a prepolymer, which could be further reacted to form thermosetting resins.

关键词： cardanol epoxidation aminohydrin aniline ionic liquid aniline-formaldehyde

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配位不饱和Au-O-Ti³⁺活性位点的构建及其在低温丙烯气相环氧化反应中强化氢气效率的研究 Article

宋钊宁, 闫昊, 袁俊聪, 马宏飞, 曹建琳, 王永祥, 王强, 彭冲, 邓风, 冯翔, 陈德, 杨朝合, 胡永康

《工程（英文）》 2023年第25卷第6期页码 144-156 doi: 10.1016/j.eng.2023.01.008

摘要：

自1998年以来，人们广泛认为Au/Ti基催化剂的Au-O-Ti⁴⁺位点是在相对高温条件下丙烯气相环氧化反应的活性位点，但该类催化剂的H₂有效利用率普遍较低。本工作发现了一种在相对低温条件下丙烯气相环氧化反应的新活性位点Au-O-Ti³⁺。值得注意的是，该活性位点主导反应时，最佳温度可从200 °C显著降低至138 °C，并使催化剂保持前所未有的43.6%的H₂有效利用率、90.7%的环氧丙烷（PO）选择性和超过100 h的稳定性。本工作通过调整处理后S-1晶种中Si-OH和Bu₃NH⁺的量，定量构建了Au-O-Ti³⁺活性位点。并且利用原位紫外-可见光谱（operando UV-vis）技术研究了Ti-OOH反应中间体的动态演化过程，结果表明，在Au-O-Ti³⁺活性位点上的Ti-OOH的生成速率比在Au-O-Ti⁴⁺活性位点上的明显增高。此外，氨程序升温脱附（NH₃-TPD）和X射线光电子能谱（XPS）表征以及密度泛函数理论（DFT）计算表明，在相对低温条件下，Au-O-Ti³⁺活性位点中配位不饱和Ti³⁺位点促进了Au和Ti³⁺之间的电子转移，从而增强了催化剂对O₂的吸附能力，有效促进H₂O₂的原位生成，并进一步促进活性中间体Ti-OOH的形成。本工作所报道的结果为强化丙烯直接气相环氧化反应的H₂有效利用率提供了新的思路，而且为低温下丙烯直接气相环氧化反应的工业化推进开辟了新的机会。