Grigoras, Ionela

Rosendahl, Lasse Aistrup

Toor, Saqib Sohail

Mechanisms for bio-crude formation during the conversion of glucose, xylose and glucose-xylose mixtures as biomass model compounds under hot compressed water conditions are investigated. Studies in literature have shown that the diverse products formed at the early stages of glucose or xylose conversion are 5-HMF, erythrose, glyceraldehyde, dihydroxyacetone, pyruvaldehyde, and saccharinic acids resulted through reactions such as dehydration, retro-aldol condensation and isomerization. However, these compounds are mostly water soluble compounds and lack the final steps towards formation of water insoluble components at longer reaction times. The effects of pressure, pH, catalyst and reaction time on the main products are examined thoroughly. The possible routes for the formation of oil compounds are developed

    Aalborg UniversitetReaction mechanisms and kinetics of processing glucose, xylose and glucose-xylosemixtures under hot compressed water conditions for predicting bio-crude compositionGrigoras, Ionela; Toor, Saqib Sohail; Rosendahl, Lasse AistrupPublication date:2015Document VersionPublisher's PDF, also known as Version of recordLink to publication from Aalborg UniversityCitation for published version (APA):Grigoras, I., Toor, S. S., & Rosendahl, L. A. (2015). Reaction mechanisms and kinetics of processing glucose,xylose and glucose-xylose mixtures under hot compressed water conditions for predicting bio-crudecomposition. Poster session presented at 4th International Conference on Thermochemical Conversion Science(TcBiomass 2015), Chicago, IL, United States.General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright ownersand it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.            ? Users may download and print one copy of any publication from the public portal for the purpose of private study or research.            ? You may not further distribute the material or use it for any profit-making activity or commercial gain            ? You may freely distribute the URL identifying the publication in the public portal ?Take down policyIf you believe that this document breaches copyright please contact us at vbn@aub.aau.dk providing details, and we will remove access tothe work immediately and investigate your claim.Downloaded from vbn.aau.dk on: April 30, 2017Reaction mechanism Reaction mechanisms and kinetics of processing glucose, xylose and glucose-xylose mixtures under hot compressed water conditions for predicting bio-crude composition  Ionela F. Grigoras*, Saqib S. Toor, Lasse A. Rosendahl  Aalborg University, Department of Energy Technology, Pontoppidanstræde 101, 9220 Aalborg, Denmark *ifg@et.aau.dk   Separation  process Conclusions HTL process CO₂  CO  CH₄  C₃H₈  C₄H₁₀  H₂ Water phase Oil Solids Vacuum  Filtration Solvent Evaporation Centrifugation Glucose Xylose Mixture of Glucose - Xylose 400 °C 250 – 350 bar 0 – 20 min 0 – 4 % catalyst Parametric study – Glucose case 010203040506070800 10 20Vol. % Reaction time (min) CO2CH4C4H10C3H8o Pressure and reaction time did not influence the final pH of the product significantly; Catalyst concentration was found to be the only factor affecting the final pH of the product.  o Reaction time influences gas composition; longer reaction time increased the concentration of CH₄, C₃H₈ and C₄H₁₀ in the gas phase, whereas the CO₂ decreased for glucose and mixtures of glucose-xylose, but increased in the case of xylose.   o At short reaction times furan based compounds such as furfurals,  furanones, tetrahydrofuranols  will be kept in the biocrude composition.  At longer reaction times, the furan ring opens under the water attack.  The ring opening leads to production of ketones and aldehydes.  Analysis of water soluble products and biocrude showed a decrease in the furan-methanol concentration as the reaction time was increased during the HTLprocess. At the same time, the concentration of 4-hydroxy-4-methyl-2-pentanone increased. Long reaction times also favor formation of carboxylic acids.   Mechanisms for bio-crude formation during the conversion of glucose, xylose and glucose-xylose mixtures as biomass model compounds under hot compressed water conditions are investigated. Studies in literature have shown that the diverse products formed at the early stages of glucose or xylose conversion are 5-HMF, erythrose, glyceraldehyde, dihydroxyacetone, pyruvaldehyde, and saccharinic acids resulted through reactions such as dehydration, retro-aldol condensation and isomerization. However, these compounds are mostly water soluble compounds and lack the final steps towards formation of water insoluble components at longer reaction times. The effects of pressure, pH, catalyst and reaction time on the main products are examined thoroughly. The possible routes for the formation of oil compounds are developed.  01020304050250 275 300 325 350Yield (wt.% DM) Pressure (bar) Biocrude Solids Water ph. Gas01020304050600 1 2 3 4Yield (wt.% DM) Catalyst conc. (wt.% DM) Biocrude Solids Water ph. Gas01020304050600 5 10 15 20Yield (wt.% DM) Reaction time (min) Biocrude Solids Water ph. GasC3BO Center for BioOil grant #: 1205-00030B   www.biomass.et.aau.dk Acetic acidGlycolaldehydePolymerizationHydrogenationGlucoseXylofuranose FurfuralDehydrationDehydrationHMF- 3 H₂ O- 3 H₂ OHydrogenationTetrahydro-furan400 °CFuranH⁺  H₂ OFormic acidCondensationGases CO₂, CO, H₂, CH₄, C₃H₈, C₄H₁₀ KetonesPhenolics & AromaticsCokeAcidsOtto Mønsteds Fond 

Reaction mechanisms and kinetics of processing glucose, xylose and glucose-xylose mixtures under hot compressed water conditions for predicting bio-crude composition

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Reaction mechanisms and kinetics of processing glucose, xylose and glucose-xylose mixtures under hot compressed water conditions for predicting bio-crude composition

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