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Opedal, Mihaela TanaseORCID iD iconorcid.org/0000-0003-0140-1693
Publications (10 of 22) Show all publications
Ghoreishi, S., Løhre, C., Hermundsgård, D. H., Lindgaard Molnes, J., Tanase Opedal, M., Brusletto, R. & Barth, T. (2024). Identification and quantification of valuable platform chemicals in aqueous product streams from a preliminary study of a large pilot-scale steam explosion of woody biomass using quantitative nuclear magnetic resonance spectroscopy. Biomass Conversion and Biorefinery, 14, 3331
Open this publication in new window or tab >>Identification and quantification of valuable platform chemicals in aqueous product streams from a preliminary study of a large pilot-scale steam explosion of woody biomass using quantitative nuclear magnetic resonance spectroscopy
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2024 (English)In: Biomass Conversion and Biorefinery, ISSN 2190-6815, E-ISSN 2190-6823, Vol. 14, p. 3331-Article in journal (Refereed) Published
Abstract [en]

Steam explosion breaks down the polymeric matrix and enables the recovery of valuable compounds from lignocellulosic feedstock. In the steam explosion process, biomass is treated with high-pressure steam which subsequently generates large quantities of a condensed aqueous liquid (process effluent) and a filtered aqueous liquid (filtrate) that contain furfural, 5-hydroxymethylfurfural, 5-methylfurfural, methanol, and acetic acid as major constituents. This study addresses the identification and quantification of value-added chemicals in the aqueous product streams using quantitative analytical nuclear magnetic resonance spectroscopy with water suppression. This work reports a screening study for two different types of sawdust (Norway spruce and birch) at two different scales (4 L and 10 L reactors) using different reaction temperatures (190–223 °C) and corresponding pressures (13–24 bar), with and without the addition of SO2 gas. The duration of all experiments was 8 min. The process effluents contained acetic acid, methanol, formic acid, 5-methylfurfural, and furfural. Acetic acid (0.5 g/kg dry input biomass) and furfural (1.0 g/kg dry input biomass) were more abundant than methanol, formic acid, and 5-methylfurfural for both feedstocks. The addition of SO2 increased the furfural yields, indicating more efficient hydrolysis of hemicelluloses under acidic conditions. Filtrate samples also contained 5-hydroxymethylfurfural, with the highest concentrations (5.7–6.0 g/kg dry input biomass) in the filtrates from spruce. The different feedstocks and steam explosion temperatures strongly influenced the overall yields of the target compounds, in some cases tripling the concentrations. The results can be used to improve the profit margins in a pellets and chemicals biorefinery, as demonstrated in the ArbaOne pellets plant. © 2022, The Author(s).

Place, publisher, year, edition, pages
Springer Science and Business Media Deutschland GmbH, 2024
Keywords
5-Hydroxymethylfurfural, Aqueous product streams, Biorefinery, Furfural, Lignocellulosic biomass, Steam explosion, Acetic acid, Chemicals, Effluents, Explosions, Feedstocks, Filtration, Formic acid, Hydrogen bonds, Nuclear magnetic resonance, Nuclear magnetic resonance spectroscopy, pH, Refining, Sodium hydroxide, Steam, 'Dry' [, 5 hydroxymethyl furfurals, 5-methylfurfural, Aqueous liquids, Aqueous product stream, Biorefineries, Pilot scale, Platform chemicals, Product streams, Biomass
National Category
Ecology
Identifiers
urn:nbn:se:ri:diva-59245 (URN)10.1007/s13399-022-02712-w (DOI)2-s2.0-85129017913 (Scopus ID)
Note

Funding details: 509-42/16; Funding details: Horizon 2020 Framework Programme, H2020, 818349; Funding details: Norges Forskningsråd, 226244/F50, 309970; Funding details: Bergens Forskningsstiftelse, BFS-NMR-1; Funding text 1: Open access funding provided by University of Bergen (incl Haukeland University Hospital). This work received funding from Arbaflame AS through the Research Council of Norway under grant agreement No 309970 and the European Union’s Horizon 2020 research and innovation programme under grant agreement No 818349.; Funding text 2: The authors gratefully acknowledge Lund University Biobased Industry Research Center and Kai Toven at RISE PFI AS for providing samples. This work was partly supported by Bergen Research Foundation (BFS-NMR-1), Sparebankstiftinga Sogn og Fjordane (509-42/16), and the Research Council of Norway through the Norwegian NMR Platform, NNP (226244/F50).

Available from: 2022-05-24 Created: 2022-05-24 Last updated: 2024-06-10Bibliographically approved
Ruwoldt, J., Syverud, K. & Opedal, M. T. (2024). Purification of soda lignin. Sustainable Chemistry for the Environment, 6, Article ID 100102.
Open this publication in new window or tab >>Purification of soda lignin
2024 (English)In: Sustainable Chemistry for the Environment, ISSN 2949-8392, Vol. 6, article id 100102Article in journal (Refereed) Published
Abstract [en]

Purity of technical lignin is one of the main obstacles in the utilization of lignin to value-added chemicals, products, and materials. The objective of this study was to investigate and compare single and two stage purification methods for obtaining soda lignin with high purity. Extensive washing and extraction with water was found effective, increasing the abundance of acid insoluble lignin while reducing its ash content. Extraction with organic solvents was conducted with 2-propanol or blends of n-heptane/1-butanol or cyclohexane/acetone. These solvents were shown to have little effect on the total lignin content, as determined by wet-chemical methods. Two-stage treatments (washing with water followed by solvent extraction) were hence not better than single stage water extraction in terms of the lignin purity. Still, selective removal of low molecular weight components after solvent extraction was noted, reducing the overall polydispersity of the lignin. Evaporation at 40 °C also showed little effect, whereas calcination at 150 °C significantly increased the molecular weight of the soda lignin. The latter effect was explained by thermally induced cross-linking. In addition, the UV absorbance of the calcinated lignin increased, which is likely related to changes in the aromatic structure. Such effect also entailed that UV/vis spectrophotometry was found less reliable in determining the total lignin content. At last, a mathematical model was adapted to predict the total lignin content from FTIR spectrometry. In conclusion, the tested procedures can be used to purify soda lignin and adjust its molecular weight.

Place, publisher, year, edition, pages
Elsevier B.V., 2024
National Category
Chemical Sciences
Identifiers
urn:nbn:se:ri:diva-73301 (URN)10.1016/j.scenv.2024.100102 (DOI)2-s2.0-85191834330 (Scopus ID)
Note

This work was carried out as a part of project “LignoWax – Green Wax Inhibitors and Production Chemicals based on Lignin”, Grant no. 326876. The authors gratefully acknowledge the financial support from the Norwegian Research Council, Equinor ASA, and ChampionX Norge AS. 

Available from: 2024-06-03 Created: 2024-06-03 Last updated: 2024-06-03Bibliographically approved
Opedal, M. T., Ghoreishi, S., Hermundsgård, D. H., Barth, T., Moe, S. T. & Brusletto, R. (2024). Steam explosion of lignocellulosic residues for co-production of value-added chemicals and high-quality pellets. Biomass and Bioenergy, 181, Article ID 107037.
Open this publication in new window or tab >>Steam explosion of lignocellulosic residues for co-production of value-added chemicals and high-quality pellets
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2024 (English)In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 181, article id 107037Article in journal (Refereed) Published
Abstract [en]

The demand of pellets as energy carrier and the competitiveness of wood biomass are the drivers for finding alternative raw materials for production of pellets. The aim of this study was to investigate the steam explosion of lignocellulosic residues such as, straw, sawdust birch, sawdust spruce, GROT (mixture of 30 % bark and 70 % industrial chips), and their mix to co-production of value-added chemicals and high-quality pellets. The raw materials were first impregnated with water/acetic acid prior to steam explosion process, while leaching and washing of steam exploded biomass was used to reduce the ash content. The value-added chemicals were extracted with MIBK, and a gas chromatography was used to determine which value-added chemicals are present in the MIBK filtrates after extraction of the steam exploded biomass. Thermogravimetric analysis and Fourier transform infrared spectroscopy, elemental analysis, calorific values, compression strength and density were used to assess and compare the quality of steam exploded biomass and pellets quality. The results from the extraction experiments shows that furfural, HMF, vanillin, syringaldehyde and coniferaldehyde are the most value-added chemicals extracted from lignocellulosic residues where higher yield of the valuable chemicals was obtained when the biomass was presoaked in acetic acid. The ash content was reduced by 83 % for straw material by washing and leaching of steam exploded straw material when the biomass was presoaked in acetic acid. High quality pellets with high calorific value (20 MJ/kg), high compression strength (228 kN/m), high density (1300 kg/m3) and low ash content (0,06 %) were produced from sawdust spruce and GROT:Spruce mix used in our study. Based on our results, we can therefore suggest that steam explosion process of lignocellulosic residues improves the quality of the biomass to pellets production and at the same time open for the possibility to produce value-added chemicals. 

Place, publisher, year, edition, pages
Elsevier Ltd, 2024
Keywords
Bio-chemicals, Extraction, Lignocellulosic biomass, Pellets, Steam explosion, Acetic acid, Biomass, Explosions, Fourier transform infrared spectroscopy, Gas chromatography, Industrial chemicals, Leaching, Pelletizing, pH, Quality control, Steam, Thermogravimetric analysis, Washing, Ash contents, Chemical quality, Co-production, High quality, Lignocellulosic residues, Pellet, Value-added chemicals, compression, wood
National Category
Materials Engineering
Identifiers
urn:nbn:se:ri:diva-71989 (URN)10.1016/j.biombioe.2023.107037 (DOI)2-s2.0-85182416565 (Scopus ID)
Funder
The Research Council of Norway, 309674The Research Council of Norway, 309970The Research Council of Norway, 321268
Note

 Correspondence Address: M. Tanase-Opedal; RISE PFI AS, Trondheim, Høgskoleringen 6B, N-7491, Norway; This work received founding from Arbaflame AS through the Research Council of Norway under grant agreement No 309970; No 309674 and PhD project No 321268. 

Available from: 2024-02-22 Created: 2024-02-22 Last updated: 2024-02-22Bibliographically approved
Ruwoldt, J., Chinga Carrasco, G. & Opedal, M. T. (2024). Sustainable Materials from Organosolv Fibers and Lignin, Kraft Fibers, and Their Blends. Polymers, 16(3), Article ID 377.
Open this publication in new window or tab >>Sustainable Materials from Organosolv Fibers and Lignin, Kraft Fibers, and Their Blends
2024 (English)In: Polymers, E-ISSN 2073-4360, Vol. 16, no 3, article id 377Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to investigate new materials from organosolv fibers, organosolv lignin, kraft fibers, and their blends. The organosolv fibers showed reprecipitated lignin on the surface, a comparably low fiber length of 0.565 mm on average, and a high fines content of 82.3%. Handsheets were formed and thermopressed at 175 °C and 50 MPa, yielding dense materials (1050–1100 kg/m3) with properties different to that of regular paper products. The thermopressing of organosolv fibers alone produced materials with similar or better tensile strength (σb = 18.6 MPa) and stiffness (E* = 2.8 GPa) to the softwood Kraft reference pulp (σb = 14.8 MPa, E* = 1.8 GPa). The surface morphology was also smoother with fewer cavities. As a result, the thermopressed organosolv fibers exhibited higher hydrophobicity (contact angle > 95°) and had the lowest overall water uptake. Combinations of Kraft fibers with organosolv fibers or organosolv lignin showed reduced wetting and a higher density than the Kraft fibers alone. Furthermore, the addition of organosolv lignin to Kraft fibers greatly improved tensile stiffness and strength (σb = 23.8 MPa, E* = 10.5 GPa), likely due to the lignin acting as a binder to the fiber network. In conclusion, new thermopressed materials were developed and tested, which show promising potential for sustainable fiber materials with improved water resistance.

Place, publisher, year, edition, pages
Multidisciplinary Digital Publishing Institute (MDPI), 2024
Keywords
added-lignin thermoformed pulps, green materials, Kraft pulp, molded pulp, organosolv fibers, thermoforming, Anatomy, Contact Angle, Fibers, Stiffness, Tensile Strength, Wetting, Morphology, Surface morphology, Added-lignin thermoformed pulp, Fiber length, Fines content, Kraft fibers, Moulded pulp, Organosolv, Organosolv fiber, Organosolv lignin, Sustainable materials, Lignin
National Category
Materials Engineering
Identifiers
urn:nbn:se:ri:diva-71954 (URN)10.3390/polym16030377 (DOI)2-s2.0-85184694922 (Scopus ID)
Funder
The Research Council of Norway, 257622
Note

 Correspondence Address: J. Ruwoldt; RISE PFI AS, Trondheim, Høgskoleringen 6B, 7491, Norway; This article was funded by the Research Council of Norway via the FME Centre for environmentally friendly energy research Bio4Fuel, grant number 257622.

Available from: 2024-02-27 Created: 2024-02-27 Last updated: 2024-02-27Bibliographically approved
Joseph, P., Opedal, M. T. & Moe, S. T. (2023). Polymer properties of softwood organosolv lignins produced in two different reactor systems. Biopolymers, 114(12), Article ID e23566.
Open this publication in new window or tab >>Polymer properties of softwood organosolv lignins produced in two different reactor systems
2023 (English)In: Biopolymers, ISSN 0006-3525, E-ISSN 1097-0282, Vol. 114, no 12, article id e23566Article in journal (Refereed) Epub ahead of print
Abstract [en]

Lignin, the second most abundant biopolymer on earth and with a predominantly aromatic structure, has the potential to be a raw material for valuable chemicals and other bio-based chemicals. In industry, lignin is underutilized by being used mostly as a fuel for producing thermal energy. Valorization of lignin requires knowledge of the structure and different linkages in the isolated lignin, making the study of structure of lignin important. In this article, lignin samples isolated from two types of reactors (autoclave reactor and displacement reactor) were analyzed by FT-IR, size exclusion chromatography, thermogravimetric analysis (TGA), and Py-GC-MS. The average molecular mass of the organosolv lignins isolated from the autoclave reactor decreased at higher severities, and FT-IR showed an increase in free phenolic content with increasing severity. Except for molecular mass and molecular mass dispersity, there were only minor differences between lignins isolated from the autoclave reactor and lignins isolated from the displacement reactor. Carbohydrate analysis, Py-GC–MS and TGA showed that the lignin isolated using either of the reactor systems is of high purity, suggesting that organosolv lignin is a good candidate for valorization. 

Place, publisher, year, edition, pages
John Wiley and Sons Inc, 2023
Keywords
Biomolecules; Biopolymers; Infrared spectroscopy; Lignin; Molecular mass; Pressure vessels; Size exclusion chromatography; Autoclave reactors; Infrared: spectroscopy; Organosolv lignin; Organosolv pretreatment; Polymer properties; Py-GC/MS; Pyrolysis-gc-ms; Reactor systems; Size-exclusion chromatography; Valorisation; Thermogravimetric analysis
National Category
Materials Engineering
Identifiers
urn:nbn:se:ri:diva-68010 (URN)10.1002/bip.23566 (DOI)2-s2.0-85173455732 (Scopus ID)
Note

Prajin Joseph: NTNU PhD stipend, project # 70441799 and Norwegian Research Council (Norges Forskningsråd) grant # 226247 (Norwegian national research infrastructure project NorBioLab). Mihaela Tanase‐Opedal: Norwegian Research Council (Norges Forskningsråd) grant # 257622 (Norwegian Centre for Sustainable Bio‐based Fuels and Energy, Bio4Fuels) Størker T. Moe: NTNU internal funding.

Available from: 2023-11-23 Created: 2023-11-23 Last updated: 2024-06-11Bibliographically approved
Joseph, P., Opedal, M. T. & Moe, S. (2023). The O-factor: using the H-factor concept to predict the outcome of organosolv pretreatment. Biomass Conversion and Biorefinery, 13, 6727
Open this publication in new window or tab >>The O-factor: using the H-factor concept to predict the outcome of organosolv pretreatment
2023 (English)In: Biomass Conversion and Biorefinery, ISSN 2190-6815, E-ISSN 2190-6823, Vol. 13, p. 6727-Article in journal (Refereed) Published
Abstract [en]

The H-factor, a parameter used extensively to analyze and predict the outcome of kraft pulping, is applied to organosolv pretreatment. The total solid yield after organosolv pretreatment fits well with the H-factor. The concept has been extended to apply to the individual biomass polymers using unique values for the activation energy for the depolymerization of the individual biomass polymers, giving the O-factor concept analogous to the P factor used for analyzing prehydrolysis kinetics. The results showed a linear relationship between ln(L0/L) and O-factor at an activation energy of 96 kJ/mol. The best linear fit for mannan and xylan degradation was obtained at O-factor activation energies of 104 kJ/mol and 142 kJ/mol, respectively, and the formation of furfural and 5-HMF gave a good linear fit using an O-factor activation energy of 150 kJ/mol. The O-factor is thus a useful concept for analyzing organosolv pretreatment when the temperature during pretreatment is not constant. © 2021, The Author(s).

Place, publisher, year, edition, pages
Springer Science and Business Media Deutschland GmbH, 2023
Keywords
H-factor, O-factor, Organosolv pretreatment, Softwood, Kraft pulp, Polymers, Factor activation, Linear fits, Linear relationships, Pre-hydrolysis, Pre-Treatment, Total solids, Xylan degradations, Activation energy
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:ri:diva-55695 (URN)10.1007/s13399-021-01667-8 (DOI)2-s2.0-85110618463 (Scopus ID)
Note

Funding details: Norges Teknisk-Naturvitenskapelige Universitet, NTNU; Funding details: Norges Forskningsråd; Funding details: Department of Chemical Engineering, Universiti Teknologi Petronas; Funding text 1: This project was funded by the Department of Chemical Engineering, NTNU, Trondheim. The authors would like to acknowledge RISE PFI for technical assistance and providing the laboratory facilities. This work is carried out as part of the Norwegian national research infrastructure project NorBioLab (“Norwegian Biorefinery Laboratory”) and Norwegian Centre for Sustainable Bio-based Fuels and Energy (Bio4Fuels). We gratefully acknowledge The Research Council of Norway for financial support.

Available from: 2021-08-09 Created: 2021-08-09 Last updated: 2024-05-27Bibliographically approved
Moe, S. T., Marcotullio, G., Opedal, M. T. & Brusletto, R. (2022). Formation of 5-methylfurfural and 2-acetylfuran from lignocellulosic biomass and by Cr3+-catalyzed dehydration of 6-deoxyhexoses. Carbohydrate Research, 522, Article ID 108672.
Open this publication in new window or tab >>Formation of 5-methylfurfural and 2-acetylfuran from lignocellulosic biomass and by Cr3+-catalyzed dehydration of 6-deoxyhexoses
2022 (English)In: Carbohydrate Research, ISSN 0008-6215, E-ISSN 1873-426X, Vol. 522, article id 108672Article in journal (Refereed) Published
Abstract [en]

During autocatalyzed steam explosion of lignocellulose, polysaccharides in the cell wall are hydrolyzed and dehydrated to form various furaldehydes. In addition to furfural, 5-methylfurfural and 2-acetylfuran were identified in condensates from autocatalyzed steam explosion of Scandinavian softwood (Norway spruce, Picea abies). The presence of 5-methylfurfural can be explained by an acid-catalyzed dehydration of 6-deoxyaldohexoses, which are known to be present in lignocellulosic biomass. However, the presence of 2-acetylfuran cannot be explained by previously published reaction mechanisms since the required substrate (a 1-deoxyhexose or a 1-deoxyhexosan) is not known to be present in lignocellulosic biomass. In model experiments, it was shown that 2-acetylfuran is formed from rhamnose and fucose upon heating in the presence of the Lewis acid Cr3+. Possible reaction pathways for the formation of 2-acetylfuran from 6-deoxyaldohexoses are suggested. This reaction can potentially enable the targeted production of 2-acetylfuran from renewable biomass feedstocks. © 2022 The Authors

Place, publisher, year, edition, pages
Elsevier Ltd, 2022
Keywords
Furfural, Furyl methyl ketone, Lignocellulose, Oxygen heterocycles, Reaction mechanisms, Steam explosion
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-60799 (URN)10.1016/j.carres.2022.108672 (DOI)2-s2.0-85139025903 (Scopus ID)
Note

Funding details: Norges Teknisk-Naturvitenskapelige Universitet, NTNU; Funding details: Norges Forskningsråd, 309674, 309970; Funding details: Department of Chemical Engineering, Universiti Teknologi Petronas; Funding text 1: This work has been financed by the Norwegian Research Council (project grant #s 309970 and 309674 ), ArbaFlame AS and the Department of Chemical Engineering , NTNU . Thanks to employees at the ArbaFlame pellet plant in Grasmo, Norway for providing the industrial steam explosion condensate and to Dag Helge Hermundsgård at the University of Bergen, Norway for recording the 1 H NMR spectra.

Available from: 2022-10-13 Created: 2022-10-13 Last updated: 2023-05-25Bibliographically approved
Ruwoldt, J. & Opedal, M. T. (2022). Green materials from added-lignin thermoformed pulps. Industrial crops and products (Print), 185, Article ID 115102.
Open this publication in new window or tab >>Green materials from added-lignin thermoformed pulps
2022 (English)In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 185, article id 115102Article in journal (Refereed) Published
Abstract [en]

In this article, added-lignin thermoformed pulps (ALTP) were explored as a new alternative for green materials. Technical lignin was added to mechanical pulp and subsequently thermoformed, yielding a biobased material with lignin contents above natural levels. This material was tested for its mechanical properties, water-uptake, and density. In addition, FTIR and TGA-DSC were used to characterize the lignin samples, i.e., Soda, Kraft, and hydrolysis lignin, as well as lignosulfonates. The material properties were significantly changed at 20 – 40 wt% added-lignin per dry fiber. Lignin addition increased density and reduced water-uptake and wettability. The effect on mechanical properties could vary, however, pure lignin had a more beneficial effect than hydrolysis lignin containing residual cellulose. Higher stiffness was observed for the pure lignin samples at constant or decreasing tensile strength. In conclusion, ALTP is a promising material for developing new pulp products and plastics-replacements, where the ratio and type of added-lignin may be used to fine-tune the desired characteristics. © 2022 The Authors

Place, publisher, year, edition, pages
Elsevier B.V., 2022
Keywords
Fiber-based materials, Hydrolysis lignin, Kraft lignin, Lignin, Lignosulfonates, Soda lignin, Thermoforming, Density (specific gravity), Hydrolysis, Tensile strength, Bio-based materials, Fibre-based materials, Green materials, Hydrolysis lignins, Lignin contents, Water uptake, salt, secondary metabolite, stiffness, Hot Forming
National Category
Materials Engineering
Identifiers
urn:nbn:se:ri:diva-60005 (URN)10.1016/j.indcrop.2022.115102 (DOI)2-s2.0-85131223944 (Scopus ID)
Note

Funding text 1: The authors gratefully acknowledge the financial support from the Trøndelag County Council.

Available from: 2022-10-07 Created: 2022-10-07 Last updated: 2023-05-25Bibliographically approved
Hermundsgård, D. H., Ghoreishi, S., Opedal, M. T., Brusletto, R. & Barth, T. (2022). Investigating solids present in the aqueous stream during STEX condensate upgrading—a case study. Biomass Conversion and Biorefinery
Open this publication in new window or tab >>Investigating solids present in the aqueous stream during STEX condensate upgrading—a case study
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2022 (English)In: Biomass Conversion and Biorefinery, ISSN 2190-6815, E-ISSN 2190-6823Article in journal (Refereed) Epub ahead of print
Abstract [en]

Steam explosion (STEX) of woody biomass is an efficient pretreatment method in the production of water-resistant wood pellets. The STEX process also generates an aqueous condensate stream containing dissolved organic compounds, with furfural as the most abundant and valuable component. An industrial-scale recovery process for furfural and other organic by-products is therefore in the process of being developed and built. One challenge in the process has turned out to be the formation of solid particulate matter that can clog filters in the process unit. We have analyzed both the solid deposits and the fluids present at different points in the process unit to try to identify the origin of the particles using spectroscopic and chromatographic analysis, elemental analysis, and scanning electron microscopy. The aqueous fluids deriving from condensed steam contain furfural and other small organic molecules, with a separate low-density organic layer occurring at some points. This layer largely consists of wood extractives, typically terpenoids. In addition, a heavy organic phase comprising mostly furfural was found at one sampling point. The particles comprise a black, largely insoluble material with a H/C ratio of 0.88 and an O/C ratio of 0.26 and a very low ash content. IR spectra show a low content of C–H functional groups, and chromatographic analysis supports an interpretation that the particles are dominantly furfural-sourced humin-like polymers with adsorbed or co-polymerized terpenoids. Particle formation has been reproduced in a laboratory setting with conditions similar to those in the full-scale process. © 2022, The Author(s).

Place, publisher, year, edition, pages
Springer Science and Business Media Deutschland GmbH, 2022
Keywords
Biorefinery, Condensate, Furfural, Steam explosion, Terpenoids, Aldehydes, Chromatographic analysis, Lipids, Scanning electron microscopy, Spectroscopic analysis, Biorefineries, Case-studies, Pretreatment methods, Process unit, Water resistant, Wood pellet, Woody biomass
National Category
Engineering and Technology
Identifiers
urn:nbn:se:ri:diva-61553 (URN)10.1007/s13399-022-03593-9 (DOI)2-s2.0-85143212740 (Scopus ID)
Note

Funding details: 509-42/16; Funding details: Universitetet i Bergen, UiB; Funding details: Norges Forskningsråd, 226244/F50, 309970, 321268; Funding details: Bergens Forskningsstiftelse, BFS-NMR-1; Funding text 1: Open access funding provided by University of Bergen (incl Haukeland University Hospital) This work received funding from Arbaflame AS through the Research Council of Norway under grant agreement No 309970 and Ph.D. project No 321268.; Funding text 2: The authors would like to acknowledge Siv Dundas for assisting with the ICP-MS analysis, Irene Heggestad at the ELMilab for assistance with the SEM imaging, Inger J. Fjellanger for assistance with the elemental analysis, and Kenneth Aasarød from RISE PFI for assistance with the TGA-FTIR analysis. We would also like to thank Stine Johansen at the ArbaOne plant for assistance with on-site work and Joakim L. Molnes for his graphical contribution and help with text revision. This work was partly supported by the Bergen Research Foundation (BFS-NMR-1), Sparebankstiftinga Sogn og Fjordane (509-42/16), and the Research Council of Norway through the Norwegian NMR Platform, NNP (226244/F50).

Available from: 2022-12-19 Created: 2022-12-19 Last updated: 2024-05-27Bibliographically approved
Joseph, P., Ottesen, V., Opedal, M. T. & Moe, S. T. (2022). Morphology of lignin structures on fiber surfaces after organosolv pretreatment. Biopolymers, 113(9), Article ID e23520.
Open this publication in new window or tab >>Morphology of lignin structures on fiber surfaces after organosolv pretreatment
2022 (English)In: Biopolymers, ISSN 0006-3525, E-ISSN 1097-0282, Vol. 113, no 9, article id e23520Article in journal (Refereed) Published
Abstract [en]

The redeposition of lignin to the fiber surface after organosolv pretreatment was studied using two different reactor types. Results from the conventional autoclave reactor suggest that redeposition occurs during the cooling down stage. Redeposited particles appeared to be spherical in shape. The size and population density of the particles depends on the concentration of organosolv lignin in the cooking liquor, which is consistent with the hypothesis that reprecipitation of lignin occurs when the system is cooled down. The use of a displacement reactor showed that displacing the spent cooking liquor with fresh cooking liquor helps in reducing the redeposition and the inclusion of a washing stage with fresh cooking liquor reduced the reprecipitation of lignin, particularly on the outer fiber surfaces. Redeposition of lignin was still observed on regions that were less accessible to washing liquid, such as fiber lumens, suggesting that complete prevention of redeposition was not achieved. © 2022 The Authors. 

Place, publisher, year, edition, pages
John Wiley and Sons Inc, 2022
Keywords
lignin morphology, lignin redeposition, organosolv pretreatment, SEM analysis of fiber surface, Fibers, Lignin, Particle size analysis, Population statistics, Surface morphology, Washing, Cooking liquor, Fibre surfaces, Lignin structure, Re-precipitation, Redeposition, SEM analyse of fiber surface, SEM analysis, Morphology
National Category
Production Engineering, Human Work Science and Ergonomics
Identifiers
urn:nbn:se:ri:diva-60033 (URN)10.1002/bip.23520 (DOI)2-s2.0-85132576291 (Scopus ID)
Note

Funding details: Norges Teknisk-Naturvitenskapelige Universitet, NTNU; Funding details: Norges Forskningsråd, 295864; Funding details: Department of Chemical Engineering, Universiti Teknologi Petronas; Funding text 1: This project was funded by the Department of Chemical Engineering, NTNU, Trondheim, and the Department of Chemical Engineering is acknowledged for funding the Ph.D. fellowship of Prajin Joseph, and the postdoctoral fellowship of Vegar Ottesen. The authors would like to acknowledge RISE PFI for technical assistance and providing the laboratory facilities. This work is carried out as part of the Norwegian national research infrastructure project NorBioLab (“Norwegian Biorefinery Laboratory”) and the Norwegian Centre for Sustainable Bio‐based Fuels and Energy (Bio4Fuels). We gratefully acknowledge The Research Council of Norway for the support to the Norwegian Micro‐ and Nano‐Fabrication Facility, NorFab, project number 295864.

Available from: 2022-10-04 Created: 2022-10-04 Last updated: 2023-07-06Bibliographically approved
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