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Showing 1 to 18 of 18 for “"Levulinic Acid"”.
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Production of levulinic acid in urban biorefineries
… has not previously been commercialized, uses acid-catalyzed hydrolysis of the carbohydrate feedstock to produce levulinic acid, a noted "platform chemical" that provides three main benefits: (1) convertibility from diverse and heterogeneous carbohydrate feedstocks containing the high moisture …
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Kinetics of Methyl Ketone and Levulinic Acid Oxidative Scission Over Supported Vanadium Oxide Catalysts
<p>Levulinic acid (LA) is a platform chemical derived from lignocellulosic biomass. Among the various applications LA has in industrial commodities and specialty chemicals, we previously reported a novel pathway that converts LA to maleic anhydride (MA) in high yields through methyl a-carbon …
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Gas Phase Oxidation of Levulinic Acid for the Production of Maleic Anhydride over Supported Vanadium Oxide Catalysts
… context, we examine the aerobic oxidation of levulinic acid, a bio-based platform chemical derived from lignocellulosic biomass, to produce maleic anhydride, a valuable commodity chemical. This process is carried out over supported vanadium oxide catalysts. Yields as high as 71% of the …
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Evaluation of erythrocyte amino levulinic acid dehydratase as an indicator of chronic lead exposure in wild populations of rainbow trout
The activity of erythrocyte amino levulenic acid dehydratase (ALA-D) and liver and bone lead concentrations were measured in 141 wild rainbow trout from two highway-influenced and two pristine streams. A significant relationship between ALA-D activity and liver lead concentrations among streams (r …
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Transformation of biomass carbohydrates by transition metal catalysts
… 5-(Hydroxymethyl)-2-furfuraldehyde (HMF) and levulinic acid. Iron (III) chloride hexahydrate has shown moderate activity to transform glucose into HMF and has also shown high yields and selectivity for the production of levulinic acid. Typically synthesized from acidic solutions made with …
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Hidrogenação de ácido levulínico a gama-valerolactona empregando fosfetos de metais de transição suportados em sílica
… were prepared, characterized and evaluated for levulinic acid hydrogenation to γ- valerolactone: Ni2P, CoP, MoP, WP and Fe2P. The catalysts were prepared in two steps: phosphate synthesis by incipient wetness followed by calcination, and phosphide synthesis by in situ temperature programmed …
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Electrostatic Atomization Of Antimicrobial Treatments On Ground Beef Processing, Instrumental Color, Sensory Color, Taste and Aroma Characteristics
… Antimicrobial treatments included: fumaric acid, malic acid, octanoic acid, decanoic acid, sodium propionate, propionic acid solution, potassium lactate/diacetate blend, sodium benzoate, hexanoic acid, pyruvic acid, levulinic acid, lactic acid/ citric acid blend, sodium diacetate, lemon …
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Catalytic Conversion of Cellulose to Carboxylic Acids through Aqueous Phase Partial Oxidation
… through oxidation reactions to carboxylic acids with high selectivity. Noble metal loaded metal oxides and metal oxides were tested for their catalytic activity in the process. Gold nanoparticle loading was found to promote a yield of 12% by carbon weight of lactic acid as a result of Lewis …
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Effect of maleic acid on the selectivity of glucose and fructose dehydration and degradation
… This study focuses on the Lewis and Brønsted acid effect on hexose dehydration for HMF production. We report the positive effect of maleic acid, a dicarboxylic acid used as Brønsted acid, on the selectivity of hexose dehydration to 5-hydroxymethyfurfural (HMF), and subsequent hydrolysis to …
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Kinetics of ketone hydrogenation over supported Ru catalysts
… (GVL) via the aqueous phase hydrogenation of levulinic acid (LA) over supported Ru catalysts was carried out, in order to understand how to better design a hydrogenation catalyst for such biomass catalytic strategies. At temperatures representative of biomass processing, the reaction proceeds …
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Process Study, Simulation, and Optimization of the Direct Conversion of Biomass to Ethyl Levulinate
… sustainable production of fuels and chemicals. Levulinic acid (LA) is considered to be a versatile platform chemical which can be derived from biomass and further upgraded to high-value products like levulinate esters. In this work, the direct chemical conversion of lignocellulosic biomass to …
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Synthesis, Selection, And Optimization Of Doped Zeolite Catalyst For The Nonbiological Production Of Lactic Acid Derivatives From Biomass Derived Carbohydrates
… project is to chemically synthesize fatty acids, hydrocarbons, other fuel constituents, or high value chemicals directly from biomass-derived carbohydrates (e.g. sugars generated using processes developed for the cellulosic ethanol industry). This work will look specifically at synthesizing …
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Non-Covalent Interactions in Polymeric Materials: From Ionomers to Polymer Blends
… deep eutectic solvents, choline chloride : malic acid (ChCl:MA) and L-arginine : levulinic acid (Arg:LA), have been demonstrated as effective plasticizers for poly(vinyl alcohol) (PVOH) films. The plasticization effects on the properties of PVOH films were evidenced by lower crystallizability and …
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Hydrothermal Liquefaction of Plastic as an Alternative Recycling Method
… methanolysis producing 1,4-benzenedicarboxylic acid, dimethyl ester. This reaction pathway is in competition with the hydrolysis and glycolysis pathways that produce ethylene glycol, benzoic acid, and bis(2-hydroxyethyl) terephthalate; thus, resulting a lower concentration of these compounds …
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Transformation of biomass to value-added chemicals through non-thermal plasma
… polar aprotic solvents and diluted sulfuric acid in the absence of external heating. A levoglucosenone (LGO) yield of 43 mol% could be obtained after 15 min of conversion in γ-valerolactone (GVL) by applying a voltage of 6 kV and frequency of 6 kHz. With sulfolane as the solvent, a 38 mol% …
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Exploring hydrothermal reactions : from prebiotic synthesis to green chemistry
… employed as a basis. They can be transformed to levulinic acid and formic acid, which can both react via a transfer hydrogenation to the green solvent and biofuel gamma-valerolactone. This second reaction usually requires catalysis by Ru or Pd, which are neither sustainable nor low-priced. Under …
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Control of pathogenic bacteria in Queso Fresco by using generally recognized as safe ingredients
… agents included nisin (Nisaplin®), caprylic acid, trans-cinnamaldehyde, monolaurin, carvacrol, eugenol, levulinic acid, orange-terpenes, d-limonene, eucalyptol, thymol, and clove essential oils. Batches of queso fresco were inoculated with mixtures of approximately 104 CFU/g of different L. …
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Techno-economic analysis of furfural derivatives in integrated sugarcane biorefineries
… such as 5-hydroxymethylfurfural (HMF), levulinic acid (LA), and 1,4-butanediol (1,4-BDO). Process simulations were developed to generate mass and energy balances, which were used to estimate the capital and operating expenses of each biorefinery. The minimum selling price (MSP) required …