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1.
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
2.
环境友好催化剂催化葡萄糖水解的研究 总被引:3,自引:2,他引:1
研究了n(SiO2)∶n(Al2O3)=20~25的ZRP-5分子筛(催化剂1)、n(SiO2)∶n(Al2O3)=30的ZRP- 5分子筛(催化剂2)、甲酸、液态水四种催化剂分别催化葡萄糖水解。研究发现,葡萄糖水解机理复杂,产物众多,水解主产物为乙酰丙酸(LA),同时还有5 羟甲基糠醛(HMF)、果糖、乳酸、甲酸、呋喃甲醛等副产物生成。不同的催化剂对葡萄糖的转化率影响不大,但各个反应产物收率相差很大。HMF的生成比较容易,而LA的生成相对困难。ZRP-5分子筛催化剂对LA具有良好的选择性。 相似文献
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4.
Bifunctional Solid Catalysts for the Selective Conversion of Fructose to 5-Hydroxymethylfurfural 总被引:2,自引:0,他引:2
Anthony J. Crisci Mark H. Tucker James A. Dumesic Susannah L. Scott 《Topics in Catalysis》2010,53(15-18):1185-1192
Solid catalysts based on SBA-15 silica were designed for the conversion of fructose to 5-hydroxymethylfurfural (HMF). The catalysts incorporate thioether groups that may promote the tautomerization of fructose to its furanose form, as well as sulfonic acid groups to catalyze its dehydration. The materials were characterized by elemental analysis, X-ray diffraction, N2 adsorption/desorption, and solid-state 13C and 29Si CP/MAS NMR spectroscopy. Functional groups incorporated into mesoporous silica by co-condensation are more robust under the reaction conditions (water at 180 °C) than those grafted onto a non-porous silica. The bifunctional mesoporous catalyst achieved a selectivity for HMF of 74% at 66% fructose conversion. 相似文献
5.
T. Dallas Swift Christina Bagia Vladimiros Nikolakis Dionisios G. Vlachos George Peklaris Paul Dornath Wei Fan 《American Institute of Chemical Engineers》2013,59(9):3378-3390
5‐hydroxymethylfurfural (HMF) can be produced from the acid‐catalyzed dehydration of fructose, but its yield is limited due to subsequent HMF degradation to side products. A reactive adsorption process is proposed to improve the yield to HMF. Separate experimental single‐component isotherms of fructose, HMF, formic acid, and levulinic acid on carbon BP2000 and reaction kinetics of the fructose dehydration to HMF in aqueous solution of HCl are presented to develop empirical isotherms and kinetic rate constants, respectively. These submodels are subsequently integrated in an adsorptive reactor at a range of temperatures (100–150°C) with different loadings of adsorbent. It is shown that the adsorbent improves HMF yield compared to the single‐solution phase (adsorbent‐free case). Low temperatures and high‐adsorbent loadings improve HMF yield. Under certain conditions both reactive adsorption and the commonly used reactive extraction can result in a similar improvement in HMF yield. HMF recovery from the solid adsorbent has been identified as a major challenge that can be ameliorated through adsorbent and solvent selection. The framework outlined here can be applied to any aqueous phase chemistry where the desired product is an intermediate in a reaction cascade. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3378–3390, 2013 相似文献
6.
Nikolay V. Gromov Tatiana B. Medvedeva Oxana P. Taran Andrey V. Bukhtiyarov Cyril Aymonier Igor P. Prosvirin Valentin N. Parmon 《Topics in Catalysis》2018,61(18-19):1912-1927
Solid acid catalysts based on graphite-like mesoporous carbon material Sibunit were developed for the one-pot solubilization–hydrolysis–dehydration of cellulose into glucose and 5-hydroxymethylfurfural (5-HMF). The catalysts were produced by treating Sibunit surface with three different procedures to form acidic and sulfo groups on the catalyst surface. The techniques used were: (1) sulfonation by H2SO4 at 80–250 °C, (2) oxidation by wet air or 32 v/v% solution of HNO3, and (3) oxidation-sulfonation what meant additional sulfonating all the oxidized carbons at 200 °C. All the catalysts were characterized by low-temperature N2 adsorption, titration with NaOH, TEM, XPS. Sulfonation of Sibunit was shown to be accompanied by surface oxidation (formation of acidic groups) and the high amount of acidic groups prevented additional sulfonation of the surface. All the Sibunit treatment methods increased the surface acidity in 3–15 times up to 0.14–0.62 mmol g?1 compared to pure carbon (0.042 mmol g?1). The catalysts were tested in the depolymerization of mechanically activated microcrystalline cellulose at 180 °C in pure water. The main products 5-HMF and glucose were produced with the yields in the range of 8–22 wt% and 12–46 wt%, respectively. The maximal yield were achieved over Sibunit sulfonated at 200 °C. An essential difference in the composition of main products obtained with solid acid Sibunit carbon catalysts (glucose, 5-HMF) and soluble in water H2SO4 catalysts (formic and levulinic acids) as well as strong dependence of the reaction kinetics on the morphology of carbon catalysts argue for heterogenious mechanism of cellulose depolymerization over Sibunit. 相似文献
7.
A novel route for green conversion of cellulose to HMF by cascading enzymatic and chemical reactions
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Yunlei Zhang Pei Jin Meng Liu Jianming Pan Yongsheng Yan Yao Chen Qingang Xiong 《American Institute of Chemical Engineers》2017,63(11):4920-4932
In this work, a novel route to deconstruct cellulose into 5‐hydroxymethylfurfural (HMF) by cascading enzymatic and chemical reactions is reported. For biocatalyst preparation, Fe3O4 nanoparticles encapsulated SBA‐15 with appropriate pore size was synthesized and utilized as magnetic scaffolds for the immobilization of cellulase. For chemical catalyst preparation, sulfated zirconium dioxide conformed monolayers were grafted on SBA‐15 template to create thermally robust mesoporous catalysts with tunable solid basic/Lewis acid and Brønsted acid sites. Catalytic performance of biocatalyst and chemical catalyst was explored in the aqueous phase conversion of IL pretreated cellulose to glucose, and in the iPrOH/water solvent conversion of glucose to HMF conversion, respectively. After the optimization of reaction conditions, a sequential conversion of pretreated cellulose to glucose and glucose to HMF was performed, and 43.6% HMF yield can be obtained. The cascaded enzymatic and chemocatalytic reaction system demonstrates an effective and economically friendly process for biomass energy conservation. A novel route for green conversion of IL pretreated cellulose to 5‐hydroxymethylfurfural (HMF) by cascading an enzymatic catalysis in an aqueous system with chemocatalysis in an iPrOH/water solvent mixture is reported. © 2017 American Institute of Chemical Engineers AIChE J, 2017 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
10.
The direct hydrolysis of cellulose to glucose, HMF and other soluble by-products at 190 °C in water solution using zeolites (H-BEA, H-MOR), sulphated zirconia supported over mesoporous silica (SBA-15), Amberlyst®15, heteropolyacids and AlCl3·6H2O as acid catalysts was studied using a high cellulose to catalyst ratio (10), not-pretreated (neither mechanically nor chemically) cellulose and a static (not mixed) autoclave. Under these conditions, not usually considered, but relevant for industrial applications, micro and mesoporous solid acid catalysts are active in the direct hydrolysis of cellulose to glucose, HMF and other soluble by-products. The reactivity in crystalline cellulose conversion is determined on one side from the need to realize an efficient solid-solid interaction between the external surface of the catalyst and the crystalline cellulose, and on the other side on the need to limit the secondary reactions of the formed products. Microporous materials, due to the presence of shape-selectivity effects limiting the polymerization of glucose to humic-type species show the highest formation of glucose and HMF with respect to the sulphated zirconia supported over mesoporous silica (SBA-15) and homogeneous heteropoly acids. 相似文献
11.
Pan Wang Lianhai Ren Qingyu Lu Yanbing Huang 《Chemical Engineering Communications》2016,203(11):1507-1514
The dehydration of glucose into 5-hydroxymethylfurfural (HMF) was catalyzed by NKC-9 (a macroporous sulfonated polystyrene ion-exchange resin) combined with metal oxides (TiO2, ZrO2, Al2O3 calcined at different temperatures). In the combined catalytic system, Al2O3 calcined at 550°C exhibited excellent catalytic activity, when the dosage of NKC-9 was kept constant. Four parameters (catalyst dosage, reaction temperature, reaction time, and initial glucose amount) were optimized by employing response surface methodology (RSM), with HMF yield as the response parameter. The maximum HMF yield of 62.09% was obtained at catalyst 0.07 g, temperature 140°C, time 20 min, and glucose 0.01 g. The catalytic activity of the binary catalyst (NKC-9 and Al2O3) for the conversion of glucose into HMF did not show significant decrease after five-times uses at 140°C for 20 min. 相似文献
12.
Zirconium doped mesoporous KIT-6 samples with different Si/Zr ratios were synthesized by the direct hydrothermal method. Various characterization techniques confirm that highly distributed ZrO2 nanoparticles and multi-coordinated Zr4+ species are incorporated in the mesoporous composites. One-pot synthesis of 5-hydroxymethylfurfura(HMF) from glucose was examined in the presence of Zr-KIT-6(20) the molar ratio of Si to Zr is 20 under aqueous system. The effects of temperature, reaction time, catalyst dosage and biphasic solvent system on the conversion of glucose and the HMF yield were investigated. It was found that the glucose conversion and the HMF yield have been improved from 54.8% to 79.0% and from 19.5% to 34.5% in the biphasic MIBK-water system, respectively. Both the acidity of Zr-KIT-6(20) and the biphasic MIBK-water system are responsible for the improved performance of glucose dehydration to HMF. 相似文献
13.
Yao Zhong Cuiying Huang Jianxin Cai Jun Wang Zheling Zeng Qiang Deng 《American Institute of Chemical Engineers》2023,69(2):e17890
The conversion of macromolecular saccharides (fructose, glucose, sucrose, and inulin) to 5-hydroxymethylfurfural (HMF) is often limited by the mass transfer resistance of existing catalysts. Herein, a two-dimensional metal–organic framework (NUS-8-PhSO3H) containing high densities of dual acidic sites (Lewis and Brønsted acid sites) was developed for the first time by diazo grafting. Characterization results and reaction kinetics showed that the rapid molecular diffusion leads to an unusual pseudozeroth reaction order and a considerably lower apparent activation energy for the fructose reaction over NUS-8-PhSO3H in contrast to the first order and higher activation energy over three-dimensional counterpart (NUS-16-PhSO3H) and reported catalysts. In addition, NUS-8-PhSO3H can also produce substantially high HMF yields and has a low activation energy for other saccharides (glucose, sucrose, and inulin) by powerful tandem steps, including polysaccharide hydrolysis, glucose isomerization, and fructose dehydration. The preparation of hydrophobic acidic NUS-8-PhSO3H provides an efficient means of synthesizing HMF from various saccharides. 相似文献
14.
Sam Duck Han Jae Ho Choi Soon Young Noh Kunyik Park Soo Kyung Yoon Young Woo Rhee 《Korean Journal of Chemical Engineering》2009,26(4):1040-1046
Palladium particles supported on porous carbon of 20 and 50 nm pore diameters were prepared and applied to the direct formic
acid fuel cell (DFAFC). Four different anode catalysts with Pd loading of 30 and 50 wt% were synthesized by using impregnation
method and the cell performance was investigated with changing experimental variables such as anode catalyst loading, formic
acid concentration, operating temperature and oxidation gas. The BET surface areas of 20 nm, 30 wt% and 20 nm, 50 wt% Pd/porous
carbon anode catalysts were 135 and 90 m2/g, respectively. The electro-oxidation of formic acid was examined in terms of cell power density. Based on the same amount
of palladium loading with 1.2 or 2 mg/cm2, the porous carbon-supported palladium catalysts showed higher cell performance than unsupported palladium catalysts. The
20 nm, 50 wt% Pd/porous carbon anode catalyst generated the highest maximum power density of 75.8 mW/cm2 at 25 °C. Also, the Pd/porous carbon anode catalyst showed less deactivation at the high formic acid concentrations. When
the formic acid concentration was increased from 3 to 9 M, the maximum power density was decreased from 75.8 to 40.7 mW/cm2 at 25 °C. Due to the high activity of Pd/porous carbon catalyst, the cell operating temperature has less effect on DFAFC
performance. 相似文献
15.
This paper demonstrates two simple ways to increase 5-hydroxymethylfurfural (HMF) yield (selectivity) in fructose dehydration with various solid acid catalysts. One is a water removal from the reaction mixture by a mild evacuation at 0.97 × 105 Pa; it increases HMF yield for various catalysts (heteropoly acid, zeolite, and acidic resin). The removal of water suppresses two undesired reactions: the hydrolysis of HMF to levulinic acid and the reaction of partially dehydrated intermediates to condensation products. The other method is a decrease in the particle (bead) size of the resin (Amberlyst-15). The crushed and sieved Amberlyst-15 powder in a size of 0.15–0.053 mm shows 100% HMF yield at high fructose concentration (50 wt.% in DMSO), which is to our knowledge the highest yield to date. Near-infrared spectroscopic characterization of adsorbed water suggests that the enhanced yield can be caused by an improved removal of adsorbed water in a small-size resin particle. 相似文献
16.
Yongchai Kwon Seungmin Baek Byungwan Kwon Jinsoo Kim Jonghee Han 《Korean Journal of Chemical Engineering》2010,27(3):836-842
We investigated cell performance and performed phenomenological analyses of direct formic acid fuel cells (DFAFCs) incorporating
anode (palladium) and cathode (platinum) catalysts prepared using a new electrospray coating technique. To optimize the design
of the DFAFC, we examined the cell performance by the Pd catalyst loading and formic acid feed rate. Of Pd catalyst loaded
samples, 3 mg/cm2 sample showed the highest electrical performance with formic acid feed rate of 5 ml/min. This behavior was caused by discrepancies
in the mass transfer limitation. When the feed rate was greater than 10 mL/min, however, the 7 mg/cm2 sample provided the highest electrical performance, which was attributed to enhanced electrooxidation reactions. For comparison
of the effect of the catalyst coating method on the cell performance of DFAFC, polarization curves of the DFAFC incorporating
catalysts prepared using a conventional airspray coating method were also measured. As a result of the comparison, the electrospray
coatingused DFAFC showed better cell performance. Based on these results, the cell performance of the DFAFCs was optimized
when the catalysts using the electrospray catalyst coating were employed, the amount of Pd loaded on the anode electrode was
3 mg/cm2 (Pd thickness: ∼6 μm), and the formic acid feed rate was 10 mL/min. 相似文献
17.
Direct formic acid fuel cells (DFAFC) currently employ either Pt-based or Pd-based anode catalysts for oxidation of formic acid. However, improvements are needed in either the activity of Pt-based catalysts or the stability of Pd-based catalysts. In this study, a number of carbon-supported Pt-based and Pd-based catalysts, were prepared by co-depositing PdM (M = Bi, Mo, or V) on Vulcan® XC-72 carbon black, or depositing another metal (Pb or Sn) on a Pt/C catalyst. These catalysts were systematically evaluated and compared with commercial Pd/C, PtRu/C, and Pt/C catalysts in a multi-anode DFAFC. The PtPb/C and PtSn/C catalysts were found to show significantly higher activities than the commercial Pt/C catalyst, while the PdBi/C provided higher stability than the commercial Pd/C catalyst. 相似文献
18.
《Journal of Catalysis》2005,229(2):414-423
Surfactant-templated micro-mesoporous silicas possessing sulfonic acid groups (SAGs) have been prepared, characterized, and tested as catalysts in the dehydration of d-xylose to furfural. All of the materials possessed catalytic activity. In general, selectivity to furfural was lower for a poorly ordered microporous hybrid material, prepared via the co-condensation of (3-mercaptopropyl)trimethoxysilane with bis(trimethoxysilylethyl)benzene, than for mesoporous MCM-41 silica anchored with SAGs via postsynthesis modification. The MCM-41 material with the highest loading of SAGs (0.7 meq g−1) displayed fairly high selectivity for furfural (ca. 82% in DMSO or water/toluene mixture) at high xylose conversion (>90% within 24 h, at 140 °C). Xylose conversion increased significantly with reaction temperature. At 170 °C, more than 85% conversion was achieved within 4 h with any of the sulfonic acid-functionalized catalysts. Furfural yield tended to increase with temperature. Xylose conversion increased with increasing amount of catalyst, and for a xylose/MCM-41-SO3H ratio of 0.5, 76% conversion was achieved within 4 h, at 140 °C. Catalyst deactivation was observed after long residence times, possibly because of the interaction of reaction products with the acid sites, leading to surface loading. 相似文献
19.
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
20.
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