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1.
2,5-dimethylfuran (DMF) is a promising compound in the production of biofuel with high-quality properties. In this study, it is aimed to develop new efficient catalysts to synthesize DMF from 5-hydroxymethylfurfural (HMF). Co, Mn/Co, and Ru/Co catalysts were prepared using the NaBH4 reduction method. The catalysts were subjected to activity tests for the hydrogenation of HMF to DMF by changing the reaction parameters, such as temperature and time. Mn/Co catalysts prepared from metal precursors at various molar ratios of Mn/Co were found to be effective in hydrogenation reactions of HMF to DMF. A 91.8% DMF yield was achieved in the presence of a Mn/Co (50/50) catalyst without noble metal at 180°C for 4 hours. The Brunauer-Emmet-Teller (BET) method, x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and induction coupled plasma mass spectroscopy (ICP-MS) techniques were used to characterize the efficient Mn/Co catalyst. 相似文献
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Jing Luo Lisandra Arroyo‐Ramírez Raymond J. Gorte Despina Tzoulaki Dionisios G. Vlachos 《American Institute of Chemical Engineers》2015,61(2):590-597
The three‐phase hydrodeoxygenation reaction of 5‐hydroxymethylfurfural (HMF) with H2 was studied over a 10 wt % Pt/C catalyst using both batch and flow reactors, with ethanol, 1‐propanol, and toluene solvents. The reaction is shown to be sequential, with HMF reacting first to furfuryl ethers and other partially hydrogenated products. These intermediate products then form dimethyl furan (DMF), which in turn reacts further to undesired products. Furfuryl ethers were found to react to DMF much faster than HMF, explaining the higher reactivity of HMF when alcohol solvents were used. With the optimal residence time, it was possible to achieve yields approaching 70% in the flow reactor with the Pt/C catalyst. Much higher selectivities and yields were obtained in the flow reactor than in the batch reactor because side products are formed sequentially, rather than in parallel, demonstrating the importance of choosing the correct type of reactor in catalyst screening. © 2014 American Institute of Chemical Engineers AIChE J, 61: 590–597, 2015 相似文献
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《Journal of Industrial and Engineering Chemistry》2013,19(4):1106-1111
5-Hydroxymethyl-2-furfural (HMF) was prepared with high fructose corn syrup (HFCS) manufactured directly from industry. Equipped industrial process and cheaper availability considered HFCS-90 as a competitive starter for production of HMF. Readily evaporable solvent, 1,4-dioxane was found as a promising reaction media from the screening of various solvents and readily available cation exchange resin, Amberlyst-15 was used as a solid acid catalyst. Parametric variation studies including amount of catalyst, concentration of HFCS-90, and reaction temperature were performed to achieve a maximum HMF yield of 80% at 100 °C within 3 h. In particular, use of readily evaporable solvent and heterogeneous catalyst allowed highly practical purification of HMF, which still remains as a major obstacle to the commercialization of HMF. With filtration, evaporation, and extraction, HMF was simply isolated in 72% yield and 1H NMR spectra of the isolated HMF confirmed that its purity was sufficient for use in next step of reactions. In addition, all solvents could be recycled with distillation and catalyst was reused up to 5 cycles without a significant loss of activity. 相似文献
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Efficient Catalytic Oxidation of 5‐Hydroxymethylfurfural to 2,5‐Furandicarboxylic Acid by Magnetic Laccase Catalyst
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Dr. Ke‐Feng Wang Prof. Chun‐lei Liu Prof. Kun‐yan Sui Prof. Chen Guo Prof. Chun‐Zhao Liu 《Chembiochem : a European journal of chemical biology》2018,19(7):654-659
2,5‐Furandicarboxylic acid (FDCA) is a bio‐based platform chemical for the production of polyethylene furanoate (PEF) and other valuable furanic chemicals. A magnetic laccase catalyst with (2,2,6,6‐tetramethyl‐piperidin‐1‐yl)oxyl (TEMPO) as the mediator has the remarkable capability of oxidizing 5‐hydroxymethylfurfural (HMF) to 2,5‐furandicarboxylic acid (FDCA). Under optimal reaction conditions, a quantitative yield (90.2 %) of FDCA with complete HMF conversion was obtained after 96 h of reaction. More importantly, the magnetic laccase catalyst exhibited good recyclability and stability, maintaining 84.8 % of its original activity following six reuse cycles. This is the first report on the efficient catalytic oxidation of HMF to FDCA by using an immobilized enzyme catalyst. 相似文献
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Huan Li Yao Zhong Luxi Wang Qiang Deng Jun Wang Zheling Zeng Xinxiang Cao Shuguang Deng 《中国化学工程学报》2021,33(5):167-174
In the dehydration of fructose to 5-hydroxymethyl furfural(HMF), in situ produced water weakens the acid strength of the catalyst and causes the rehydration of HMF, causing unsatisfactory catalytic activity and selectivity. In this work, a class of benzenesulfonic acid-grafted metal–organic frameworks with strong acidity and hydrophobicity is obtained by the direct sulfonation method using 4-chlorobenzenesulfonic acid as sulfonating agent. The resultant MOFs have a specific surface area of greater than 250 m~2·g~(-1), acid density above 1.0 mmol·g~(-1), and water contact angle up to 129°. The hydrophobic MOF-Ph SO_3 H exhibits both higher catalytic activity and selectivity than MOF-SO_3 H in the HMF synthesis due to its better hydrophobicity and olephilicity. Moreover, the catalyst has a high recycled stability. At last, fructose is completely converted, and 98.0% yield of HMF is obtained under 120 °C in a DMSO solvent system. The successful preparation of the hydrophobic acidic MOF provides a novel hydrophobic catalyst for the synthesis of HMF. 相似文献
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以含有丰富金属离子的造纸污泥为原料,通过高温煅烧法制备生物炭(SBC),并与对氨基苯磺酸进行接枝,制备了一种高效碳基固体酸催化剂(S-SBC)。通过FTIR、XRD、SEM等对催化剂的组成、形貌、结构、酸负载量、比孔径及比表面积等进行表征。将该催化剂用于D-果糖转化为5-羟甲基糠醛(HMF)反应,对反应时间、反应温度、催化剂用量及溶剂种类、D-果糖质量分数等影响因素进行考察,并与用杨木为原料且采用相同方法制备的杨木炭催化剂(S-PBC)进行比较,结果表明,S-SBC的催化活性优于S-PBC。S-SBC同时含有由金属离子形成的Lewis酸位点以及—SO3H等形成的Brönsted酸位点,两种酸位点在催化D-果糖脱水制备5-羟甲基糠醛的过程中具有协同作用。S-SBC在二甲基亚砜中130 ℃下催化反应40 min, HMF收率高达95.2%。连续使用4次后,催化活性没有明显下降。 相似文献
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Heterogeneous selective oxidation of 5-hydroxymethyl-2-furfural (HMF) into 2,5-diformylfuran (DFF) using molecular oxygen and vanadium catalyst onto activated carbon in MIBK, extracting solvent for HMF, is described. Highly stable V2O5 supported on activated carbon catalyst was synthesized using V3 + (VCl3) precursor and confirmed by XPS analysis, which found to be highly active. A maximum HMF conversion of > 95% with > 96% DFF selectivity was achieved and this heterogeneous catalyst could be used 4 times without any significant loss of activity. 相似文献
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随着化石能源的日益短缺,清洁可再生生物质资源的利用,尤其是制备高品质生物燃料逐渐成为研究热点。2,5-二甲基呋喃(DMF)具有优良的物理化学性质,被认为是最有前途的液体生物燃料之一,可通过生物质平台分子5-羟甲基糠醛(HMF)选择性氢解制备。HMF化学性质非常活泼,可以转化成多种下游产品,因此设计制备高选择性催化剂对于靶向合成DMF至关重要。本文依据贵金属和非贵金属对催化剂进行分类,详细综述了非均相催化剂在HMF氢解制备DMF反应中的研究新进展;针对目前研究中存在的局限性和问题,提出了催化剂和反应体系的研究方向。此外,指出以生物质为原料直接制备DMF及建立有效的分离技术是实现DMF工业化生产的重要途径。 相似文献
10.
Catalytic dehydration of glucose to 5‐hydroxymethylfurfural with a bifunctional metal‐organic framework
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Ye Su Ganggang Chang Zhiguo Zhang Huabin Xing Baogen Su Qiwei Yang Qilong Ren Yiwen Yang Zongbi Bao 《American Institute of Chemical Engineers》2016,62(12):4403-4417
Glucose conversion to 5‐hydroxymethylfurfural (HMF) generally undergoes catalytic isomerization reaction by Lewis acids followed by the catalytical dehydration to HMF with Brönsted acid. In this work, a sulfonic acid functionalized metal‐organic framework MIL‐101(Cr)‐SO3H containing both Lewis acid and Brönsted acid sites, was examined as the catalyst for γ‐valerolactone‐mediated cascade reaction of glucose dehydration into HMF. Under the optimal reaction conditions, the batch heterogeneous reaction gave a HMF yield of 44.9% and selectivity of 45.8%. Reaction kinetics suggested that the glucose isomerization in GVL with 10 wt % water follows the second‐order kinetics with an apparent activation energy of 100.9 kJ mol?1. Continuous reaction in the fixed‐bed reactor showed that the catalyst is highly stable and able to provide a steady HMF yield. This work presents a sustainable and green process for catalytic dehydration of biomass‐derived carbohydrate to HMF with a bifunctional metal‐organic framework. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4403–4417, 2016 相似文献
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Khavinet Lourvanij Gregory L. Rorrer 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,69(1):35-44
Molecular-sieving catalysts have the potential to promote the production of oxygenated hydrocarbons from glucose. A kinetic model for the partial dehydration of glucose to organic acids by micro- and mesoporous aluminosilicate catalysts was developed. Kinetic parameters were estimated from glucose conversion and product yield versus time data at 150°C for HY-zeolite, aluminum-pillared montmorillonite, MCM-20 and MCM-41 catalyst powders of 0·5 mmol H+ g−1 solid-acid activity. Rate constants for the partial dehydration of glucose to 5-hydroxymethylfurfural (HMF) and the rehydration and cleavage of HMF to formic acid and 4-oxopentanoic acid were maximized at catalyst pore diameters of 10–30 Å. The final organic acid product yields were low, less than 60% of theoretical for formic acid and 10% of theoretical for 4-oxopentanoic acid, due to significant coke formation. © 1997 SCI. 相似文献
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Polymer-supported NHC–metal catalysts were prepared from chloromethyl polystyrene resin via two-step reaction. Metals were loaded into 1.6 – 16 mol% of total imidazolium and the remaining imidazolium chloride salt provided ionic liquid moiety. The formation of metal complex with the polymer-supported NHC ligand was analyzed by ATR FT-IR, XRD, and XPS. The synthesized polymer-supported NHC–metal catalysts were applied to the dehydration of fructose into HMF. The environmentally benign and inexpensive polymer-supported NHC–FeIII catalyst showed good catalytic activity and yielded HMF at 73% (with a conversion of 97%). It could also be reused without significant loss of catalytic activity. 相似文献
15.
The catalytic dehydration of fructose (FRU) to 5-hydroxymethylfurfural (HMF) usually runs with the formation of several side products. Among these, levulinic acid (LA) is often reported as the product of a consecutive reaction of HMF re-hydration. In this work, side reactions of the dehydration of FRU performed in very green conditions (water as solvent and niobic acid as solid catalyst) are taken into account. Experimental evidences are given that, in the used conditions: i) HMF is a final stable product, ii) no formation of LA, either deriving from a consecutive reaction of HMF or directly from FRU transformation, was observed, and iii) LA does not react to give condensation products with any other chemical species present in the reaction mixture. 相似文献
16.
Shi Shengbin Wu Yuanfeng Liu Panli Zhang Mengting Zhang Zongqi Gao Lijing Xiao Guomin 《Catalysis Letters》2022,152(4):954-961
Catalysis Letters - Synthesis of 5-hydroxymethylfurfural (HMF) from carbohydrates was achieved over the homogeneous catalyst acid poly(4-styrenesulfonic acid) (PSS). The various reaction conditions... 相似文献
17.
The production of 2,5-furandicarboxylic acid (FDCA) starting with fructose as substrate via acid-catalyzed formation and subsequent
oxidation of 5-hydroxymethylfurfural (HMF) was investigated. It was shown that an effective separation of the oxidation catalyst
from fructose in combination with extraction and derivatization of formed HMF in methyl isobutyl ketone (MIBK) leads to formation
of FDCA as final product. Two systems were developed to realize the concept, one by phase separation with a membrane, the
other by encapsulating the oxidation catalyst in silicone beads.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
18.
阿魏酸的合成及抗氧化性能的研究 总被引:4,自引:0,他引:4
以香草醛和丙二酸为原料、乙酸铵为催化剂、DMF为溶剂、苯为带水剂,合成了阿魏酸。在V(苯)∶V(DMF)=2∶1、乙酸铵用量为6%(以香草醛质量计)、n(香草醛)∶n(丙二酸)=1∶1.4、反应时间为4h的优化条件下,阿魏酸产率达到71.02%。阿魏酸的抗氧化性实验结果表明,阿魏酸对食用油脂有一定的抗氧化能力,其在油脂中的抗氧化能力优于维生素E。 相似文献
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The alcohol group of hydroxymethylfurfural (compound 1, HMF) is preferentially oxidized by dioxygen and metal/bromide catalysts [Co/Mn/Br, Co/Mn/Zr/Br; Co/Mn=Br/(Co+Mn) = 1.0 mol/mol] to form the dialdehyde, 2,5‐diformylfuran (compound 2, DFF) in 57% isolated yield. HMF can be also oxidized, via a network of identified intermediates, to the highly insoluble 2,5‐furandicarboxylic acid (compound 5, FDA) in 60% yield. For comparison, benzyl alcohol gives benzaldehyde in 80% using the same catalyst system. Over‐oxidation (to CO2) of HMF is much higher than that of the benzyl alcohol but can be greatly reduced by increasing catalyst concentration. 相似文献