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Z Zhang - One of the best experts on this subject based on the ideXlab platform.

  • one pot catalytic conversion of carbohydrates into furfural and 5 Hydroxymethylfurfural
    Catalysis Science & Technology, 2016
    Co-Authors: Peng Zhou, Z Zhang
    Abstract:

    Recently, there has been growing interest in the transformation of renewable biomass into value-added chemicals and biofuels. Among them, furfural and 5-Hydroxymethylfurfural (HMF) have received great attention as precursors in the synthesis of a lot of commodity chemicals and liquid fuels. Furfural and HMF can be easily produced from the dehydration of xylose and fructose over acid catalysts, respectively. However, the use of xylose and fructose is limited in large-scale production of furans due to their high cost. Therefore, much effort has been devoted to the synthesis of furfural from xylan and hemicelluloses and HMF from glucose based carbohydrates over different catalysts, particularly with two catalytic sites. Herein, we will provide an overview of the methods developed in recent years to synthesize furfuran and HMF from carbohydrates by using the “one-pot” strategy and discuss major challenges involved in the large scale production of furfural and HMF.

  • efficient conversion of cellulose into biofuel precursor 5 Hydroxymethylfurfural in dimethyl sulfoxide ionic liquid mixtures
    Bioresource Technology, 2014
    Co-Authors: Shaohua Xiao, Yimei Wang, Zhongfeng Fang, Z Zhang
    Abstract:

    Abstract In recent years, cellulose has received increasing attention as a potential material for the production of biofuels and bio-based chemicals. In this study, a new process for the efficient conversion of cellulose into 5-Hydroxymethylfurfural (HMF) was developed by the use of AlCl3 as the catalyst in DMSO–ionic liquid ([BMIM]Cl) mixtures. Various reaction parameters such as reaction time, reaction temperature, solvent and catalyst dosage were investigated in detail. A high HMF yield of 54.9% was obtained from cellulose at 150 °C after 9 h in a mixed solvent of DMSO–[BMIM]Cl (10 wt.%). More importantly, the catalytic system could be reused for several times despite of the slight loss of its catalytic activity.

  • catalytic conversion of carbohydrates into 5 Hydroxymethylfurfural by germanium iv chloride in ionic liquids
    Chemsuschem, 2011
    Co-Authors: Z Zhang, Qian Wang, Haibo Xie, Wujun Liu, Zongbao K Zhao
    Abstract:

    Catalytic Conversion of Carbohydrates into 5-Hydroxymethylfurfural by Germanium(IV) Chloride in Ionic Liquids

Hero J. Heeres - One of the best experts on this subject based on the ideXlab platform.

  • Dehydration of Different Ketoses and Aldoses to 5-Hydroxymethylfurfural
    ChemSusChem, 2013
    Co-Authors: Robert-jan Van Putten, Jenny N. M. Soetedjo, Evgeny A. Pidko, Jan C. Van Der Waal, Emiel J. M. Hensen, Ed De Jong, Hero J. Heeres
    Abstract:

    5-Hydroxymethylfurfural (HMF) is considered an important building block for future bio-based chemicals. Here, we present an experimental study using different ketoses (fructose, sorbose, tagatose) and aldoses (glucose, mannose, galactose) under aqueous acidic conditions (65gL(-1) substrate, 100-160 degrees C, 33-300mM H2SO4) to gain insights into reaction pathways for hexose dehydration to HMF. Both reaction rates and HMF selectivities were significantly higher for ketoses than for aldoses, which is in line with literature. Screening and kinetic experiments showed that the reactivity of the different ketoses is a function of the hydroxyl group orientation at the C3 and C4 positions. These results, in combination with DFT calculations, point to a dehydration mechanism involving cyclic intermediates. For aldoses, no influence of the hydroxyl group orientation was observed, indicating a different rate-determining step. The combination of the knowledge from the literature and the findings in this work indicates that aldoses require an isomerization to ketose prior to dehydration to obtain high HMF yields.

  • caprolactam from renewable resources catalytic conversion of 5 Hydroxymethylfurfural into caprolactone
    Angewandte Chemie, 2011
    Co-Authors: Teddy Buntara, Sebastien Noel, Pim Huat Phua, Ignacio Meliancabrera, Johannes G De Vries, Hero J. Heeres
    Abstract:

    Renewable nylon: 5-Hydroxymethylfurfural (HMF), which can be obtained from renewable resources such as D-fructose, was converted into caprolactone with very good overall selectivity in only three steps. The new route involves two hydrogenation steps to obtain 1,6-hexanediol, which was oxidatively cyclized to caprolactone, and then converted into caprolactam.

  • caprolactam from renewable resources catalytic conversion of 5 Hydroxymethylfurfural into caprolactone
    Angewandte Chemie, 2011
    Co-Authors: Teddy Buntara, Sebastien Noel, Pim Huat Phua, Ignacio Meliancabrera, Johannes G De Vries, Hero J. Heeres
    Abstract:

    In zijn dissertatie beschrijft dhr. Teddy experimentele onderzoek naar de omzetting van 5-Hydroxymethylfurfural (HMF) naar caprolactam, de uitgangsstof voor nylon 6. Het HMF kan op zijn beurt weer gemaakt worden uit lignocellulosische biomassa, zoals hout of grasachtig afval, is dan dus een groen basismateriaal. C6-suikers in lignocellulosische biomassa zijn interessante startmaterialen voor groene chemicalien met grote toepassingsmogelijkheden. HMF kan gemaakt worden uit D-fructose en mogelijk ook uit goedkopere suikers als D-glucose. Een grote uitdaging voor dit onderzoek betrof de ontwikkeling van katalytische routes voor de omzetting van HMF naar 1,6-hexanediol (1,6-HD). Vier verschillende routes zijn onderzocht: de directe hydrogenatie van HMF naar 1,6-HD, een tweestapsroute via 2,5-THF-dimethanol (THFDM), een driestapssynthese via THFDM en 1,2,6-hexanetriol (1,2,6-HT) en ten slotte een vierstapssynthese via THFDM, 1,2,6-HT en tetrahydro-2H-pyran-2-ylmethanol (2-THPM).

  • a kinetic study on the decomposition of 5 Hydroxymethylfurfural into levulinic acid
    Green Chemistry, 2006
    Co-Authors: B Girisuta, L P B M Janssen, Hero J. Heeres
    Abstract:

    Levulinic acid (LA), accessible by the acid catalyzed degradation of biomass, is potentially a very versatile green intermediate chemical for the synthesis of various (bulk) chemicals for applications like fuel additives, polymers, and resin precursors. We report here a kinetic study on one of the key steps in the conversion of biomass to levulinic acid, i.e. the reaction of 5-Hydroxymethylfurfural (HMF) to levulinic acid. The kinetic experiments were performed in a temperature window of 98–181 °C, acid concentrations between 0.05–1 M, and initial HMF concentrations between 0.1 and 1 M. The highest LA yield was 94% (mol/mol), obtained at an initial HMF concentration of 0.1 M and a sulfuric acid concentration of 1 M. The yield at full HMF conversion is independent of the temperature. An empirical rate expression for the main reaction as well as the side reaction to undesired humins was developed using the power law approach. Agreement between experimental and model data is good. The rate expressions were applied to gain insights into optimum process conditions for batch processing.

Kohki Ebitani - One of the best experts on this subject based on the ideXlab platform.

Johannes G De Vries - One of the best experts on this subject based on the ideXlab platform.

  • cyclopentanone derivatives from 5 Hydroxymethylfurfural via 1 hydroxyhexane 2 5 dione as intermediate
    Chemsuschem, 2018
    Co-Authors: Bartosz Wozniak, Anke Spannenberg, Sandra Hinze, Johannes G De Vries
    Abstract:

    An efficient strategy for the conversion of biomass derived 5-Hydroxymethylfurfural (HMF) into 2-hydroxy-3-methylcyclopent-2-enone (MCP) by an intramolecular aldol condensation of 1-hydroxyhexane-2,5-dione (HHD) has been developed. Further transformations of MCP towards the diol, enol acetate, levulinic acid and N-heterocyclic compounds are also reported.

  • caprolactam from renewable resources catalytic conversion of 5 Hydroxymethylfurfural into caprolactone
    Angewandte Chemie, 2011
    Co-Authors: Teddy Buntara, Sebastien Noel, Pim Huat Phua, Ignacio Meliancabrera, Johannes G De Vries, Hero J. Heeres
    Abstract:

    Renewable nylon: 5-Hydroxymethylfurfural (HMF), which can be obtained from renewable resources such as D-fructose, was converted into caprolactone with very good overall selectivity in only three steps. The new route involves two hydrogenation steps to obtain 1,6-hexanediol, which was oxidatively cyclized to caprolactone, and then converted into caprolactam.

  • caprolactam from renewable resources catalytic conversion of 5 Hydroxymethylfurfural into caprolactone
    Angewandte Chemie, 2011
    Co-Authors: Teddy Buntara, Sebastien Noel, Pim Huat Phua, Ignacio Meliancabrera, Johannes G De Vries, Hero J. Heeres
    Abstract:

    In zijn dissertatie beschrijft dhr. Teddy experimentele onderzoek naar de omzetting van 5-Hydroxymethylfurfural (HMF) naar caprolactam, de uitgangsstof voor nylon 6. Het HMF kan op zijn beurt weer gemaakt worden uit lignocellulosische biomassa, zoals hout of grasachtig afval, is dan dus een groen basismateriaal. C6-suikers in lignocellulosische biomassa zijn interessante startmaterialen voor groene chemicalien met grote toepassingsmogelijkheden. HMF kan gemaakt worden uit D-fructose en mogelijk ook uit goedkopere suikers als D-glucose. Een grote uitdaging voor dit onderzoek betrof de ontwikkeling van katalytische routes voor de omzetting van HMF naar 1,6-hexanediol (1,6-HD). Vier verschillende routes zijn onderzocht: de directe hydrogenatie van HMF naar 1,6-HD, een tweestapsroute via 2,5-THF-dimethanol (THFDM), een driestapssynthese via THFDM en 1,2,6-hexanetriol (1,2,6-HT) en ten slotte een vierstapssynthese via THFDM, 1,2,6-HT en tetrahydro-2H-pyran-2-ylmethanol (2-THPM).

Anders Riisager - One of the best experts on this subject based on the ideXlab platform.

  • Selective Aerobic Oxidation of 5-Hydroxymethylfurfural in Water Over Solid Ruthenium Hydroxide Catalysts with Magnesium-Based Supports
    Catalysis Letters, 2011
    Co-Authors: Yury Y. Gorbanev, Søren Kegnæs, Anders Riisager
    Abstract:

    Solid catalyst systems comprised of ruthenium hydroxide supported on magnesium-based carrier materials (spinel, magnesium oxide and hydrotalcite) were investigated for the selective, aqueous aerobic oxidation of the biomass-derived chemical 5-Hydroxymethylfurfural into 2,5-furandicarboxylic acid (FDA), a possible plastics precursor. The novel catalyst systems were characterized by nitrogen physisorption, XRPD, TEM and EDS analysis, and applied for the oxidation with no added base at moderate to high pressures of dioxygen and elevated temperatures. The effects of support, temperature and oxidant pressure were studied and optimized to allow a quantitative yield of FDA to be obtained. Graphical Abstract

  • efficient microwave assisted synthesis of 5 Hydroxymethylfurfural from concentrated aqueous fructose
    Carbohydrate Research, 2009
    Co-Authors: Thomas Sondergaard Hansen, John M Woodley, Anders Riisager
    Abstract:

    Studies on the HCl-catalysed microwave-assisted dehydration of highly concentrated aqueous fructose (27 wt%) to 5-Hydroxymethylfurfural (HMF) revealed a significant increase in the fructose conversion rate over the conventional heated systems. Water, being the most benign solvent and therefore ideal for green and sustainable chemistry, normally is a poor solvent for the dehydration process resulting in low HMF selectivities and yields. However, reaction at 200 degrees C with microwave irradiation with a short reaction time of only 1s resulted in good HMF selectivity of 63% and fructose conversion of 52%, while prolonged irradiation for 60s (or more) resulted in nearly full fructose conversion (95%) but lower HMF yield (53%). Decreasing the fructose concentration significantly improved the HMF selectivity, but possibly made the production route less attractive from an industrial point of view due to the resultant low throughput.

  • efficient microwave assisted synthesis of 5 Hydroxymethylfurfural from concentrated aqueous fructose
    Carbohydrate Research, 2009
    Co-Authors: Thomas Sondergaard Hansen, John M Woodley, Anders Riisager
    Abstract:

    Abstract Studies on the HCl-catalysed microwave-assisted dehydration of highly concentrated aqueous fructose (27 wt %) to 5-Hydroxymethylfurfural (HMF) revealed a significant increase in the fructose conversion rate over the conventional heated systems. Water, being the most benign solvent and therefore ideal for green and sustainable chemistry, normally is a poor solvent for the dehydration process resulting in low HMF selectivities and yields. However, reaction at 200 °C with microwave irradiation with a short reaction time of only 1 s resulted in good HMF selectivity of 63% and fructose conversion of 52%, while prolonged irradiation for 60 s (or more) resulted in nearly full fructose conversion (95%) but lower HMF yield (53%). Decreasing the fructose concentration significantly improved the HMF selectivity, but possibly made the production route less attractive from an industrial point of view due to the resultant low throughput.

  • gold catalyzed aerobic oxidation of 5 Hydroxymethylfurfural in water at ambient temperature
    Chemsuschem, 2009
    Co-Authors: Yury Gorbanev, Soren Kegnaes Klitgaard, John M Woodley, Claus H Christensen, Anders Riisager
    Abstract:

    The aerobic oxidation of 5-Hydroxymethylfurfural, a versatile biomass-derived chemical, is examined in water with a titania-supported gold-nanoparticle catalyst at ambient temperature (30 °C). The selectivity of the reaction towards 2,5-furandicarboxylic acid and the intermediate oxidation product 5-hydroxymethyl-2-furancarboxylic acid is found to depend on the amount of added base and the oxygen pressure, suggesting that the reaction proceeds via initial oxidation of the aldehyde moiety followed by oxidation of the hydroxymethyl group of 5-Hydroxymethylfurfural. Under optimized reaction conditions, a 71 % yield of 2,5-furandicarboxylic acid is obtained at full 5-Hydroxymethylfurfural conversion in the presence of excess base.