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James A. Dumesic - One of the best experts on this subject based on the ideXlab platform.
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selective production of Levulinic Acid from furfuryl alcohol in thf solvent systems over h zsm 5
ACS Catalysis, 2015Co-Authors: Max A Mellmer, Jean Marcel R Gallo, David Martin Alonso, James A. DumesicAbstract:Furfuryl alcohol in high concentrations (1 M) was hydrolyzed to Levulinic Acid in high yields (>70%) using H-ZSM-5 zeolite as the catalyst in monophasic tetrahydrofuran (THF)–water solvent systems. Reaction kinetics studies using H-ZSM-5 were carried out, and combined with results obtained for other Bronsted Acid catalysts, we suggest that the structural properties of H-ZSM-5, in conjunction with increased reaction performance using the polar aprotic solvent THF, are effective for furfuryl alcohol hydrolysis to Levulinic Acid while inhibiting furfuryl alcohol polymerization reactions. In addition, on the basis of results obtained for a wide range of THF–H2O solvent systems (19:1–1:2 w/w), we suggest that the hydrophobic nature of H-ZSM-5 alters the internal solvent microenvironment within the zeolite framework, allowing for high Levulinic Acid yields, even at low THF solvent concentrations (e.g., 1:2 THF–H2O w/w).
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conversion of glucose into Levulinic Acid with solid metal iv phosphate catalysts
Journal of Catalysis, 2013Co-Authors: Ronen Weingarten, James A. Dumesic, Yongtae Kim, Geoffrey A Tompsett, Alejandro Fernandez, Kee Sung Han, Edward W Hagaman, Wm Curt Conner, George W HuberAbstract:We have prepared a series of well-characterized solid Acid metal(IV) phosphate catalysts and tested them for the two-step dehydration/rehydration reaction to produce Levulinic Acid from glucose. The catalysts include zirconium (ZrP) and tin (SnP) phosphates with varying ratios of phosphorus to metal(IV). The structural, surface and bulk properties have been investigated using XRD, BET, XPS and 31P solid-state MAS NMR spectroscopy. ZrP is distinguished by a high concentration of polyphosphate species in the bulk phase, as well as increased hydroxyl groups on the surface. ZrP also shows a higher concentration of total Acid sites and Bronsted Acid sites compared to SnP, as determined by TPD measurements using gas-phase NH3 and isopropylamine. The catalyst selectivity is a function of the Bronsted to Lewis Acid site ratio using either heterogeneous or homogeneous catalysts. Catalytic activity increases with increased Lewis Acid sites. The Lewis sites mainly produce fructose via isomerization reactions and undesired degradation products (humins). HMF is produced on both Bronsted and Lewis sites, whereas Levulinic Acid is exclusively produced on Bronsted sites. Zirconium phosphate with a P/Zr molar ratio of 2 is favorable for Levulinic Acid production due to its inherently high surface area and enhanced Bronsted Acidity. This study lays the grounds for further design of improved solid Acid catalysts for aqueous phase production of HMF and Levulinic from carbohydrates.
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liquid phase catalytic transfer hydrogenation and cyclization of Levulinic Acid and its esters to γ valerolactone over metal oxide catalysts
Chemical Communications, 2011Co-Authors: Mei Chia, James A. DumesicAbstract:Levulinic Acid and its esters are converted to γ-valerolactone over metal oxide catalysts by catalytic transfer hydrogenationvia the Meerwein–Ponndorf–Verley reaction.
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production of liquid hydrocarbon fuels by catalytic conversion of biomass derived Levulinic Acid
Green Chemistry, 2011Co-Authors: Drew J Braden, Carlos A Henao, Jacob Heltzel, Christos Maravelias, James A. DumesicAbstract:Levulinic Acid derived from ligno-cellulosic biomass has the potential to be utilized as a platform intermediate molecule in the production of renewable liquid fuels for the transportation sector. Herein we report a catalytic process for the conversion of Levulinic Acid to γ-valerolactone (GVL) using a RuRe/C catalyst that is significantly more active than a traditional Ru/C catalyst. The bimetallic catalyst is active for the reduction of Levulinic Acid and simultaneous decomposition of formic Acid with good stability in the presence of sulfuric Acid, the homogeneous catalyst commonly used in the production of Levulinic Acid from carbohydrates. Results from techno-economic analyses show that the integration of this new process with catalytic decarboxylation of GVL to butene followed by alkene oligomerization could provide a cost-effective route for the conversion of ligno-cellulosic biomass to liquid hydrocarbon fuels.
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catalytic upgrading of Levulinic Acid to 5 nonanone
Green Chemistry, 2010Co-Authors: Juan Carlos Serranoruiz, Dong Wang, James A. DumesicAbstract:Aqueous solutions of Levulinic Acid can be catalytically processed, through the intermediate formation of γ-valerolactone (GVL), to an organic liquid stream that spontaneously separates from water, and is enriched in pentanoic Acid and 5-nonanone. This organic layer can serve as a source of chemicals or can be upgraded to hydrocarbon fuels.
Milford A Hanna - One of the best experts on this subject based on the ideXlab platform.
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freezing points and small scale deicing tests for salts of Levulinic Acid made from grain sorghum
Bioresource Technology, 2007Co-Authors: Girish M Ganjyal, Qi Fang, Milford A HannaAbstract:Abstract Deicers from renewable resources are needed to overcome the disadvantages of using traditional deicers. Salts made from Levulinic Acid produced using grain sorghum as raw material were tested as road deicing agents. Freezing points of these salts viz., sodium levulinate, magnesium levulinate and calcium levulinate along with rock salt (sodium chloride) were determined according to American Society for Testing and Materials (ASTM) D 1177-94 standard at concentrations of 10, 20, 30 and 40 % w/w. There were significant differences among the freezing points of the salts. Freezing points for rock salt, sodium levulinate, calcium levulinate and magnesium levulinate, for different concentrations, were in the ranges of −6.6 to −20.5, −2.9 to −15.0, −2.1 to −7.8 and −1.5 to −6.5 °C, respectively. Deicing effectiveness of the salts of Levulinic Acid were investigated by conducting small-scale deicing tests with aqueous solutions of various salt concentrations (2%, 5% and 10%) in a laboratory freezer and by spraying the deicer on a graveled surface covered by ice and snow with the average temperature during the testing at −2.7 °C. Deicing capabilities of the three salts of Levulinic Acid differed. At −2.7 °C, all three salts caused melting of the ice. Among the different levulinates studied sodium levulinate was the most effective deicing agent. These salts of levulinates could be a viable replacement for traditional deicers and could help in reducing the disadvantages of traditional deicers.
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Levulinic Acid production based on extrusion and pressurized batch reaction
Industrial Crops and Products, 2002Co-Authors: Milford A HannaAbstract:Abstract Levulinic Acid is a highly versatile chemical with numerous industrial uses, having the potential to become a commodity chemical. It can be used as a raw material for resins, plasticizers, textiles, animal feed, coatings and antifreeze. Starches and sugars are typically converted to Levulinic Acid using a batch reactor. Blends of corn starch (70%), sulfuric Acid (5%), and water (25%) were extruded using a laboratory-scale, twin-screw extruder equipped with a static mixer and a condenser. The extrudates were further reacted, under pressure, with additional water and sulfuric Acid. For any given set of reaction conditions, the Levulinic Acid yields in high amylose corn starch (HAS) samples were about 3% higher than those in normal corn starch (NS) samples. The Levulinic Acid yield increased as reaction time increased from 20 to 60 min. However, the yields in the samples containing 25% (w.b.) extruded starch and further reacted at 40 and 60 min of reaction time were not significantly different. The Levulinic Acid yield increased as the sulfuric Acid content of the secondary treatment was increased from 2 to 4%. A sulfuric Acid content greater than 0.3% by weight of starch did not increase Levulinic Acid yield. The Levulinic Acid yield increased from 7 to 47% as reaction temperature increased from 160 to 200 °C under pressure, whereas the glucose yield decreased from 77 to 0%. The Levulinic Acid yields from the extruded samples were higher than those from unextruded starch samples. The difference increased from 0.4 to 11.3% as reaction temperature increased from 160 to 200 °C. The maximum yields of glucose, hydroxymethyl furfural (HMF), and Levulinic Acid were obtained at 160, 180, and 200 °C reaction temperatures, respectively. Glucose and Levulinic Acid yields increased as extrusion temperature increased and screw speed decreased. The maximum yield of Levulinic Acid was 47.5% when extruded HAS was reacted at 200 °C after being extruded at 180 °C and 20 rpm screw speed.
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experimental studies for Levulinic Acid production from whole kernel grain sorghum
Bioresource Technology, 2002Co-Authors: Qi Fang, Milford A HannaAbstract:Levulinic Acid has potential as an important basic chemical material. This study proposed a method of making Levulinic Acid using abundant and low cost whole kernel sorghum grain as the raw material. Flour made from grinding whole kernel sorghum grains was blended with 2%, 5% and 8% aqueous solutions of sulfuric Acid. Mixtures were heated to 160 or 200 °C in a pressurized reactor. A stepwise heating scheme helped improve the yield of Levulinic Acid. Levulinic Acid yield was determined based on sorghum flour content, as opposed to total sorghum mass. Levulinic Acid yield increased as reaction temperature increased. Higher sulfuric Acid concentration also significantly increased the Levulinic Acid yield. However, flour loading had an adverse effect on Levulinic Acid yield. A maximum yield of 32.6% Levulinic Acid was achieved at 200 °C, 8% sulfuric Acid concentration and 10% flour loading. A linear regression model was capable of predicting the Levulinic Acid yield with respect to effects of reaction temperature, mineral Acid concentration and flour loading (R2=0.88).
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experimental studies for Levulinic Acid production from whole kernel grain sorghum
Bioresource Technology, 2002Co-Authors: Qi Fang, Milford A HannaAbstract:Levulinic Acid has potential as an important basic chemical material. This study proposed a method of making Levulinic Acid using abundant and low cost whole kernel sorghum grain as the raw material. Flour made from grinding whole kernel sorghum grains was blended with 2%, 5% and 8% aqueous solutions of sulfuric Acid. Mixtures were heated to 160 or 200 degrees C in a pressurized reactor. A stepwise heating scheme helped improve the yield of Levulinic Acid. Levulinic Acid yield was determined based on sorghum flour content, as opposed to total sorghum mass. Levulinic Acid yield increased as reaction temperature increased. Higher sulfuric Acid concentration also significantly increased the Levulinic Acid yield. However, flour loading had an adverse effect on Levulinic Acid yield. A maximum yield of 32.6% Levulinic Acid was achieved at 200 degrees C, 8% sulfuric Acid concentration and 10% flour loading. A linear regression model was capable of predicting the Levulinic Acid yield with respect to effects of reaction temperature, mineral Acid concentration and flour loading (R2 = 0.88).
L P B M Janssen - One of the best experts on this subject based on the ideXlab platform.
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kinetic study on the Acid catalyzed hydrolysis of cellulose to Levulinic Acid
Industrial & Engineering Chemistry Research, 2007Co-Authors: B Girisuta, L P B M JanssenAbstract:A variety of interesting bulk chemicals is accessible by the Acid-catalyzed hydrolysis of cellulose. An interesting example is Levulinic Acid, a versatile precursor for fuel additives, polymers, and resins. A detailed kinetic study on the Acid-catalyzed hydrolysis of cellulose to Levulinic Acid is reported in this paper. The kinetic experiments were performed in a temperature window of 150−200 °C, sulfuric Acid concentrations between 0.05 and 1 M, and initial cellulose intakes between 1.7 and 14 wt %. The highest yield of Levulinic was 60 mol %, obtained at a temperature of 150 °C, an initial cellulose intake of 1.7 wt %, and a sulfuric Acid concentration of 1 M. A full kinetic model covering a broad range of reaction conditions was developed using the power-law approach. Agreement between the experimental data and the kinetic model is good. The kinetic expressions were used to gain insights into the optimum process conditions for the conversion of cellulose to Levulinic Acid in continuous-reactor configu...
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a kinetic study on the decomposition of 5 hydroxymethylfurfural into Levulinic Acid
Green Chemistry, 2006Co-Authors: B Girisuta, L P B M Janssen, Hero J. HeeresAbstract: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.
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green chemicals a kinetic study on the conversion of glucose to Levulinic Acid
Chemical Engineering Research & Design, 2006Co-Authors: B Girisuta, L P B M JanssenAbstract:Levulinic Acid has been identified as a promising green, biomass derived platform chemical. A kinetic study on one of the key steps in the conversion of biomass to Levulinic Acid, i.e., the Acid catalysed decomposition of glucose to Levulinic Acid has been performed. The experiments were performed in a broad temperature window (140–200°C), using sulphuric Acid as the catalyst (0.05–1 M) and a initial glucose concentration between 0.1 and 1 M. A kinetic model of the reaction sequence was developed including the kinetics for the intermediate 5-hydroxymethyl-2-furaldehyde (HMF) and humins byproducts using a power-law approach. The yield of Levulinic Acid is favoured in dilute glucose solution at high Acid concentration. On the basis of the kinetic results, continuous reactor configurations with a high extent of back-mixing are preferred to achieve high Levulinic Acid yields.
B Girisuta - One of the best experts on this subject based on the ideXlab platform.
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kinetics of Levulinic Acid and furfural production from miscanthus giganteus
Bioresource Technology, 2013Co-Authors: Karla Dussan, B Girisuta, Donncha Haverty, James J Leahy, M H B HayesAbstract:Abstract This study investigated the kinetics of Acid hydrolysis of the cellulose and hemicellulose in Miscanthus to produce Levulinic Acid and furfural under mild temperature and high Acid concentration. Experiments were carried out in an 8 L-batch reactor with 9%-wt. biomass loading, Acid concentrations between 0.10 and 0.53 M H 2 SO 4 , and at temperatures between 150 and 200 °C. The concentrations of xylose, glucose, furfural, 5-hydroxymethylfurfural and Levulinic Acid were used in two mechanistic kinetic models for the prediction of the performance of ideal continuous reactors for the optimisation of Levulinic Acid and the concurrent production of furfural. A two-stage arrangement was found to maximise furfural in the first reactor (PFR – 185 °C, 0.5 M H 2 SO 4 , 27.3%-mol). A second stage leads to Levulinic Acid yields between 58% and 72%-mol at temperatures between 160 and 200 °C.
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kinetic study on the Acid catalyzed hydrolysis of cellulose to Levulinic Acid
Industrial & Engineering Chemistry Research, 2007Co-Authors: B Girisuta, L P B M JanssenAbstract:A variety of interesting bulk chemicals is accessible by the Acid-catalyzed hydrolysis of cellulose. An interesting example is Levulinic Acid, a versatile precursor for fuel additives, polymers, and resins. A detailed kinetic study on the Acid-catalyzed hydrolysis of cellulose to Levulinic Acid is reported in this paper. The kinetic experiments were performed in a temperature window of 150−200 °C, sulfuric Acid concentrations between 0.05 and 1 M, and initial cellulose intakes between 1.7 and 14 wt %. The highest yield of Levulinic was 60 mol %, obtained at a temperature of 150 °C, an initial cellulose intake of 1.7 wt %, and a sulfuric Acid concentration of 1 M. A full kinetic model covering a broad range of reaction conditions was developed using the power-law approach. Agreement between the experimental data and the kinetic model is good. The kinetic expressions were used to gain insights into the optimum process conditions for the conversion of cellulose to Levulinic Acid in continuous-reactor configu...
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a kinetic study on the decomposition of 5 hydroxymethylfurfural into Levulinic Acid
Green Chemistry, 2006Co-Authors: B Girisuta, L P B M Janssen, Hero J. HeeresAbstract: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.
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green chemicals a kinetic study on the conversion of glucose to Levulinic Acid
Chemical Engineering Research & Design, 2006Co-Authors: B Girisuta, L P B M JanssenAbstract:Levulinic Acid has been identified as a promising green, biomass derived platform chemical. A kinetic study on one of the key steps in the conversion of biomass to Levulinic Acid, i.e., the Acid catalysed decomposition of glucose to Levulinic Acid has been performed. The experiments were performed in a broad temperature window (140–200°C), using sulphuric Acid as the catalyst (0.05–1 M) and a initial glucose concentration between 0.1 and 1 M. A kinetic model of the reaction sequence was developed including the kinetics for the intermediate 5-hydroxymethyl-2-furaldehyde (HMF) and humins byproducts using a power-law approach. The yield of Levulinic Acid is favoured in dilute glucose solution at high Acid concentration. On the basis of the kinetic results, continuous reactor configurations with a high extent of back-mixing are preferred to achieve high Levulinic Acid yields.
Yan Gong - One of the best experts on this subject based on the ideXlab platform.
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oxidative decarboxylation of Levulinic Acid by cupric oxides
Molecules, 2010Co-Authors: Yan Gong, Lu Lin, Jianbin Shi, Shijie LiuAbstract:In this paper, cupric oxides was found to effectively oxidize Levulinic Acid (LA) and lead to the decarboxylation of Levulinic Acid to 2-butanone. The effects of cupric oxide dosage, reaction time and initial pH value were investigated in batch experiments and a plausible mechanism was proposed. The results showed that LA decarboxylation over cupric oxides at around 300 °C under Acidic conditions produced the highest yield of butanone (67.5%). In order to elucidate the catalytic activity of cupric oxides, XRD, AFM, XPS and H2-TPR techniques was applied to examine their molecular surfaces and their effects on the reaction process.
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catalytic conversion of cellulose to Levulinic Acid by metal chlorides
Molecules, 2010Co-Authors: Lincai Peng, Lu Lin, Junhua Zhang, Junping Zhuang, Beixiao Zhang, Yan GongAbstract:The catalytic performance of various metal chlorides in the conversion of cellulose to Levulinic Acid in liquid water at high temperatures was investigated. The effects of reaction parameters on the yield of Levulinic Acid were also explored. The results showed that alkali and alkaline earth metal chlorides were not effective in conversion of cellulose, while transition metal chlorides, especially CrCl(3), FeCl(3) and CuCl(2) and a group IIIA metal chloride (AlCl(3)), exhibited high catalytic activity. The catalytic performance was correlated with the Acidity of the reaction system due to the addition of the metal chlorides, but more dependent on the type of metal chloride. Among those metal chlorides, chromium chloride was found to be exceptionally effective for the conversion of cellulose to Levulinic Acid, affording an optimum yield of 67 mol % after a reaction time of 180 min, at 200 degrees C, with a catalyst dosage of 0.02 M and substrate concentration of 50 wt %. Chromium metal, most of which was present in its oxide form in the solid sample and only a small part in solution as Cr3+ ion, can be easily separated from the resulting product mixture and recycled. Finally, a plausible reaction scheme for the chromium chloride catalyzed conversion of cellulose in water was proposed.
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catalytic conversion of cellulose to Levulinic Acid by metal chlorides
Molecules, 2010Co-Authors: Lincai Peng, Lu Lin, Junhua Zhang, Junping Zhuang, Beixiao Zhang, Yan GongAbstract:Abstract: The catalytic performance of various metal chlorides in the conversion of cellulose to Levulinic Acid in liquid water at high temperatures was investigated. The effects of reaction parameters on the yield of Levulinic Acid were also explored. The results showed that alkali and alkaline earth metal chlorides were not effective in conversion of cellulose, while transition metal chlorides, especially CrCl 3 , FeCl 3 and CuCl 2 and a group IIIA metal chloride (AlCl 3 ), exhibited high catalytic activity. The catalytic performance was correlated with the Acidity of the reaction system due to the addition of the metal chlorides, but more dependent on the type of metal chloride. Among those metal chlorides, chromium chloride was found to be exceptionally effective for the conversion of cellulose to Levulinic Acid, affording an optimum yield of 67 mol % after a reaction time of 180 min, at 200 °C, with a catalyst dosage of 0.02 M and substrate concentration of 50 wt %. Chromium metal, most of which was present in its oxide form in the solid sample and only a small part in solution as Cr
