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  • 1.
    Adeboye, Peter Temitope
    et al.
    Chalmers University of Technology, Sweden.
    Bettiga, Maurizio
    Chalmers University of Technology, Sweden.
    Aldaeus, Fredrik
    RISE., Innventia.
    Larsson, Per Tomas
    RISE., Innventia.
    Olsson, Lars
    RISE., Innventia. Chalmers University of Technology, Sweden.
    Catabolism of coniferyl aldehyde, ferulic acid and p-coumaric acid by Saccharomyces cerevisiae yields less toxic products2015Ingår i: Microbial Cell Factories, ISSN 1475-2859, E-ISSN 1475-2859, Vol. 14, nr 1, artikel-id 149Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Lignocellulosic substrates and pulping process streams are of increasing relevance to biorefineries for second generation biofuels and biochemical production. They are known to be rich in sugars and inhibitors such as phenolic compounds, organic acids and furaldehydes. Phenolic compounds are a group of aromatic compounds known to be inhibitory to fermentative organisms. It is known that inhibition of Sacchromyces cerevisiae varies among phenolic compounds and the yeast is capable of in situ catabolic conversion and metabolism of some phenolic compounds. In an approach to engineer a S. cerevisiae strain with higher tolerance to phenolic inhibitors, we selectively investigated the metabolic conversion and physiological effects of coniferyl aldehyde, ferulic acid, and p-coumaric acid in Saccharomyces cerevisiae. Aerobic batch cultivations were separately performed with each of the three phenolic compounds. Conversion of each of the phenolic compounds was observed on time-based qualitative analysis of the culture broth to monitor various intermediate and final metabolites. Result: Coniferyl aldehyde was rapidly converted within the first 24 h, while ferulic acid and p-coumaric acid were more slowly converted over a period of 72 h. The conversion of the three phenolic compounds was observed to involved several transient intermediates that were concurrently formed and converted to other phenolic products. Although there were several conversion products formed from coniferyl aldehyde, ferulic acid and p-coumaric acid, the conversion products profile from the three compounds were similar. On the physiology of Saccharomyces cerevisiae, the maximum specific growth rates of the yeast was not affected in the presence of coniferyl aldehyde or ferulic acid, but it was significantly reduced in the presence of p-coumaric acid. The biomass yields on glucose were reduced to 73 and 54 % of the control in the presence of coniferyl aldehyde and ferulic acid, respectively, biomass yield increased to 127 % of the control in the presence of p-coumaric acid. Coniferyl aldehyde, ferulic acid and p-coumaric acid and their conversion products were screened for inhibition, the conversion products were less inhibitory than coniferyl aldehyde, ferulic acid and p-coumaric acid, indicating that the conversion of the three compounds by Saccharomyces cerevisiae was also a detoxification process. Conclusion: We conclude that the conversion of coniferyl aldehyde, ferulic acid and p-coumaric acid into less inhibitory compounds is a form of stress response and a detoxification process. We hypothesize that all phenolic compounds are converted by Saccharomyces cerevisiae using the same metabolic process. We suggest that the enhancement of the ability of S. cerevisiae to convert toxic phenolic compounds into less inhibitory compounds is a potent route to developing a S. cerevisiae with superior tolerance to phenolic compounds.

  • 2.
    Aldaeus, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    The Bioeconomy Research Programme 2018-20202018Ingår i: The 8th Nordic Wood Biorefinery Conference: NWBC 2018: proceedings / [ed] Hytönen Eemeli, Vepsäläinen Jessica, Espoo: VTT Technical Research Centre of Finland , 2018, s. 83-Konferensbidrag (Övrigt vetenskapligt)
  • 3.
    Aldaeus, Fredrik
    et al.
    RISE., Innventia.
    Dedic, Dina
    RISE., Innventia.
    Karpenja, Tatjana
    RISE., Innventia.
    Magnusson, Mikael
    RISE., Innventia.
    Modorato-Rosta, Caroline
    RISE., Innventia.
    Rosén, Fredrik
    RISE., Innventia.
    Sundin, Konstantin
    RISE., Innventia.
    Lindström, Mikael
    RISE., Innventia.
    Lucisano, Marco
    RISE., Innventia.
    Towards a cellulose-based society: current trends, future scenarios, and the role of the wood biorefinery2016Ingår i: Proceedings of the 14th European workshop on lignocellulosics and pulp, 2016, Vol. 2, s. 125-127Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    There is a great need to maintain research for a future in which the traditional value chains of the forest industry are combined with the needs and demands of a bio-based economy. In such a future, the pulp mill biorefinery will be a crucial node. In order to map the transformation from a fossil-based society to a cellulose-based society, a global consumer survey has been made. In addition, interviews and workshops with various players throughout the bio-economy field have been accomplished. Several current trends that affect the road to a cellulose-based society have been identified. These trends are describing the effects of urbanization, consumer behaviour, new business models, material recycling, open innovation, and the need for early demonstration of new research. The trends have been combined with uncertainties into a number of plausible scenarios describing the society and the role of cellulose in the year 2030.

  • 4.
    Aldaeus, Fredrik
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi.
    Dedic, Dina
    RISE - Research Institutes of Sweden, Bioekonomi.
    Karpenja, Tatjana
    RISE - Research Institutes of Sweden, Bioekonomi.
    Magnusson, Mikael
    RISE - Research Institutes of Sweden, Bioekonomi.
    Rosén, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi.
    Sundin, Konstantin
    RISE - Research Institutes of Sweden, Bioekonomi.
    Lindström, Mikael
    RISE - Research Institutes of Sweden, Bioekonomi.
    Lucisano, Marco
    RISE - Research Institutes of Sweden, Bioekonomi.
    Modorato-Rosta, Caroline
    RISE - Research Institutes of Sweden, Bioekonomi.
    Towards a cellulose-based society: current market and consumer trends2017Ingår i: The 7th Nordic Wood Biorefinery Conference held in Stockholm, Sweden, 28-30 Mar. 2017: NWBC 2017, Stockholm: RISE Bioekonomi , 2017, s. 1-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    It has been proposed that the future of the forest industry will involve the traditional value chains combined with the needs and demands of a bio-based economy. A global consumer survey was undertaken, together with interviews and workshops with various representatives through the bio-economy. Sources also included in-depth literature studies and research reviews. Based on this input, several current trends have been identified that will affect the route towards a cellulose-based society. These trends describe the effects of urbanization, consumer behaviour, new business models, material recycling, open innovation and the necessity for early demonstration of new research. Four different but equally plausible scenarios have been identified describing the society and the role of cellulose in 2030, highlighting the role of the wood-based biorefinery.

  • 5.
    Aldaeus, Fredrik
    et al.
    RISE., Innventia.
    Larsson, Karolina
    RISE., Innventia.
    Stevanic Srndovic, Jasna
    RISE., Innventia.
    Kubat, Mikaela
    RISE., Innventia.
    Karlström, Katarina
    RISE., Innventia.
    Norberg, Lars
    RISE., Innventia.
    Anadolyan, Shant
    RISE., Innventia.
    Peciulyte, Ausra
    Chalmers University of Technology, Sweden.
    Olsson, Lisbeth
    Chalmers University of Technology, Sweden.
    Larsson, Per Tomas
    RISE., Innventia.
    The supramolecular structure of cellulose-rich wood and wheat straw pulps can be a determinative factor for enzymatic hydrolysability2016Ingår i: The 7th Workshop on cellulose, regenerated cellulose and cellulose derivatives, 2016, s. 39-39, artikel-id 11Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Conversion of biomass to biofuels and other products is a research area that is currently attracting a great amount of interest, particularly because such production may be envisaged as a key part of any bio-based economy. Lignocellulosic biomass is abundant and sustainable, and can therefore potentially support large-scale production of biofuel as an alternative to petroleum-based fuel.

    The enzymatic hydrolysability of three industrial pulps, five lab made pulps, and one microcrystalline cellulose powder was assessed using commercial cellulolytic enzymes. To gain insight into the factors that influence the hydrolysability, a thorough characterization of the samples was done, including their chemical properties (cellulose content, hemicellulose content, lignin content, and kappa number), their macromolecular properties (peak molar mass, number-average molar mass, weight-average molar mass, polydispersity, and limiting viscosity) and their supramolecular properties (fibre saturation point, specific surface area, average pore size, and crystallinity). The hydrolysability was assessed by determination of initial conversion rate and final conversion yield, with conversion yield defined as the amount of glucose in solution per unit of glucose in the substrate. Multivariate data analysis revealed that for the investigated samples the conversion of cellulose to glucose was mainly dependent on the supramolecular properties, such as specific surface area and average pore size. The molar mass distribution, the crystallinity, and the lignin content of the pulps had no significant effect on the hydrolysability of the investigated samples.

    In addition, experiments were carried out aiming at identifying suitable conditions for pre-treatment of wheat straw, for the purpose of making cellulose rich pulps with improved enzymatic reactivity. Two sets of conditions for pre-treatment of wheat straw were identified; a combination of low temperature alkaline washing and acid pre-hydrolysis, or high temperature acid pre-hydrolysis. Both bleached wheat straw pulps showed similar enzymatic reactivity. However, the enzymatic reactivity of both bleached wheat straw pulps was found to be significantly less than what has been achieved for wood pulps. A probable explanation for the low enzymatic reactivity of the bleached wheat straw pulp can be the small pore size, limiting the access for enzymes to the cellulose surfaces in the fibre wall interior.Text, figures and tables in an extended abstract (< 4 pages with title and references).

  • 6.
    Aldaeus, Fredrik
    et al.
    RISE., Innventia.
    Larsson, Karolina
    RISE., Innventia.
    Stevanic Srndovic, Jasna
    RISE., Innventia.
    Kubat, Mikaela
    RISE., Innventia.
    Karlström, Katarina
    RISE., Innventia.
    Peciulyte, Ausra
    Chalmers University of Technology, Sweden.
    Olsson, Lilsbeth
    Chalmers University of Technology, Sweden.
    Larsson, Per Tomas
    RISE., Innventia.
    The supramolecular structure of cellulose-rich wood pulps can be a determinative factor for enzymatic hydrolysability2015Ingår i: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 22, nr 6, s. 3991-4002Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The enzymatic hydrolysability of three industrial pulps, five lab made pulps, and one microcrystalline cellulose powder was assessed using commercial cellulolytic enzymes. To gain insight into the factors that influence the hydrolysability, a thorough characterization of the samples was done, including their chemical properties (cellulose content, hemicellulose content, lignin content, and kappa number), their macromolecular properties (peak molar mass, number-average molar mass, weight-average molar mass, polydispersity, and limiting viscosity) and their supramolecular properties (fibre saturation point, specific surface area, average pore size, and crystallinity). The hydrolysability was assessed by determination of initial conversion rate and final conversion yield, with conversion yield defined as the amount of glucose in solution per unit of glucose in the substrate. Multivariate data analysis revealed that for the investigated samples the conversion of cellulose to glucose was mainly dependent on the supramolecular properties, such as specific surface area and average pore size. The molar mass distribution, the crystallinity, and the lignin content of the pulps had no significant effect on the hydrolysability of the investigated samples.

  • 7.
    Aldaeus, Fredrik
    et al.
    RISE., Innventia.
    Larsson, Karolina
    RISE., Innventia.
    Stevanic Srndovic, Jasna
    RISE., Innventia.
    Kubat, Mikaela
    RISE., Innventia.
    Karlström, Katarina
    RISE., Innventia.
    Peciulyte, Ausra
    Olsson, Lisbeth
    The influence of various pulp properties on the enzymatic hydrolyzability2014Konferensbidrag (Refereegranskat)
  • 8.
    Aldaeus, Fredrik
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi. RISE., Innventia.
    Olsson, Anne-Mari
    RISE - Research Institutes of Sweden, Bioekonomi. RISE., Innventia.
    Stevanic Srndovic, Jasna
    RISE - Research Institutes of Sweden, Bioekonomi. RISE., Innventia.
    Miniaturized determination of ash content in kraft lignin samples using oxidative thermogravimetric analysis2017Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 32, nr 2, s. 280-282Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A study has been made of several aspects of determination of ash content in kraft lignin samples using thermogravimetric analysis (TGA). Three different methods were used; with the main differences between the methods being that two have a temperature hold at 250 deg C to remove volatiles and that the three methods use different maximum temperatures, namely 525, 550 and 575 deg C, respectively. The three kraft lignins used were produced using the LignoBoost lignin isolation process. It has been demonstrated that the results obtained by the different temperature programmes showed no significant difference. The results were comparable with those from using oven ignition. Moreover, the limit of quantification was several orders of magnitude lower than when using oven ignition. It has been recommended that if TGA is used for determination of ash content, a temperature programme from a standard method should be used, which should be mentioned together with the results. The temperature programme in method one (corresponding to ISO 1762) was the shortest and the preferable method. A well as requiring less labour due to fewer movements in the analytical protocol, the TGA methods enabled a high sample throughput due to autosampling possibilities.

  • 9.
    Aldaeus, Fredrik
    et al.
    RISE., Innventia.
    Olsson, Anne-Mari
    RISE., Innventia.
    Stevanic Srndovic, Jasna
    RISE., Innventia.
    Miniaturized determination of ash content in kraft lignin samples using thermogravimetric analysis2015Ingår i: 18th International Symposium on Wood, Fiber and Pulping Chemistry, September 9-11, 2015, Vienna, 2015, s. 352-354Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Thermogravimetric analysis (TGA) in oxidative conditions is a promising alternative to ignition in oven for the determination of inorganic residue, commonly referred to as ash. It is here shown that TGA can be used with temperature programs resembling those in standardized methods for oven ignition, and obtainequivalent results even though the sample amount is several orders of magnitude lower. The precision and limit of quantification of TGA is also discussed.

  • 10.
    Aldaeus, Fredrik
    et al.
    RISE., Innventia.
    Schweinebarth, Hannah
    RISE., Innventia.
    Jacobs, Anna
    RISE., Innventia.
    Simplified determination of Klason lignin in black liquor and lignin samples2010Ingår i: 11th European workshop on lignocellulosics and pulp: EWLP 2010, 2010, s. 45-48Konferensbidrag (Övrigt vetenskapligt)
  • 11.
    Aldaeus, Fredrik
    et al.
    RISE., Innventia.
    Schweinebarth, Hannah
    RISE., Innventia.
    Törngren, Per
    RISE., Innventia.
    Jacobs, Anna
    RISE., Innventia.
    Simplified determination of total lignin content in kraft lignin samples and black liquors2011Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, nr 4, s. 601-604Artikel i tidskrift (Refereegranskat)
  • 12.
    Chedid, Fadia
    et al.
    RISE., Innventia.
    Aldaeus, Fredrik
    RISE., Innventia.
    Jacobs, Anna
    RISE., Innventia.
    Lignin molecular mass determined using size-exclusion chromatography and MALDI-TOF mass spectrometry2014Konferensbidrag (Refereegranskat)
  • 13. Gebremeskel, G G
    et al.
    Aldaeus, Fredrik
    RISE., Innventia.
    Jacobs, Anna
    RISE., Innventia.
    Determination of lignin content in kraft black liquors using capillary zone electrophoresis2014Konferensbidrag (Refereegranskat)
  • 14.
    Jacobs, Anna
    et al.
    RISE., Innventia. RISE - Research Institutes of Sweden.
    Aldaeus, Fredrik
    RISE., Innventia.
    Lignin and hemicellulose characterization for the biorefinery2014Konferensbidrag (Refereegranskat)
  • 15.
    Jacobs, Anna
    et al.
    RISE., Innventia.
    Aldaeus, Fredrik
    RISE., Innventia.
    Lignin properties for the biorefinery, and their analytical challenges2015Ingår i: NWBC 2015: The 6th Nordic Wood Biorefinery Conference, Espoo: VTT , 2015, s. 203-204Konferensbidrag (Refereegranskat)
    Abstract [en]

    The lack of official standardised methods for lignin has meant that the results from analysis of lignin properties are largely dependent on which method or laboratory that is used. Therefore, relevant and harmonised analytical methods are essential to allow producers of biorefinery products to prepare specifications for their products and to improve the possibilities for systematic development of process and product. The current status of the most important methods for lignin characterisation has been evaluated together with method development or method adaption in order to meet the requirements for high-value lignin products.

  • 16.
    Jacobs, Anna
    et al.
    RISE., Innventia.
    Aldaeus, Fredrik
    RISE., Innventia.
    Chedid, Fadia
    RISE., Innventia.
    Molecular mass distribution of lignin from black liquor: methods comparison2014Konferensbidrag (Refereegranskat)
  • 17.
    Jacobs, Anna
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi.
    Aldaeus, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi.
    Gagne, Alain
    FPInnovations, Canada.
    Kouisni, Lamfeddal
    FPInnovations, Canada; University Mohammed VI Polytechnic, Morocco.
    Liitia, Tiina
    VTT Technical Research Centre of Finland Ltd, Finland.
    Mikkelson, Atte
    VTT Technical Research Centre of Finland Ltd, Finland.
    Paleologou, Michael
    FPInnovations, Canada.
    Regnell Andersson, Sofia
    RISE - Research Institutes of Sweden, Bioekonomi.
    Tamminen, Tanja
    VTT Technical Research Centre of Finland Ltd, Finland.
    Mitigating trade barriers by standardized determination of lignin molar mass2017Ingår i: The 7th Nordic Wood Biorefinery Conference held in Stockholm, Sweden, 28-30 Mar. 2017: NWBC 2017, Stockholm: RISE Bioekonomi , 2017, s. 98-103Konferensbidrag (Refereegranskat)
    Abstract [en]

    RISE Bioeconomy, FPInnovations and VTT Technical Research Centre of Finland Ltd are working on a draft for an official ISO method for the determination of lignin molar mass. The draft will include two methods that can be used by different laboratories as reference methods, which are based on organic and aqueous size exclusion chromatography (SEC). Four samples of kraft lignin of different origin were analysed by three laboratories using the current in-house methods as well as a harmonised analytical setup. It was clear that the results differed largely between the different methods, for example, the weight average molar mass (Mw) for the LignoForce softwood lignin (LF-SW) ranged from 3,300 t0 11,100g/mol using the different methods. Harmonisation of aqueous SEC was successful. The method comprises SEC using 0l.1M sodium hydroxide as the mobile phase, a mobile phase flow rate of 0.5mL/min, Waters columns MCX 1,000A and 100,000A in series and calibration/calculation using polystyrene sulphonate standards using a linear fit. However, organic SEC was more complex and would require further investigations. Although the aqueous SEC analysis was repeatable, it was concluded that a strategy for data evaluation should be developed in order to achieve a method applicable for quality assessments.

  • 18.
    Regnell Andersson, Sofia
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Rönnols, Jerk
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Aldaeus, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Jacobs, Anna
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Lignin Bimodality: Fact or Artefact?2018Ingår i: 15th European workshop on lignocellulosics and pulp: Proceedings for oral presentations, 2018, s. 97-100Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Size Exclusion Chromatography (SEC) of lignin poses many challenges. In numerous studies chromatograms of lignin show a bimodal molar mass distribution. Is this a true characteristic of lignin, is it caused by molecular associations or aggregations, or could it could be an artefact from using column combinations with porosities that do not match properly? To improve resolution and enable separation over a larger molar mass range, multiple columns with different porosities are often connected in series. If the porosities do not match properly, the result appears as a shoulder or bimodality in the chromatogram. To understand whether the bimodal distribution is a sample characteristic or an analyze artefact, we have used different columns, column combination and samples to see when the results is a bimodal distribution and when only one peak is formed. Results show that the bimodality of lignin can be an artifact originating from column mismatch. Using single porosity columns with a low molar mass cut-off should be avoided since it can cause false bimodality.

  • 19.
    Rönnols, Jerk
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi.
    Aldaeus, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi.
    Jacobs, Anna
    RISE - Research Institutes of Sweden, Bioekonomi.
    Freichels, Helene
    Magritek, Germany.
    Danieli, Ernesto
    Magritek, Germany.
    Benchtop NMR measurements on kraft lignin2017Ingår i: 19th International symposium on wood, fibre and pulping chemistry, August 28 - September 1, 2017, Porto Seguro, Brazil, 2017, s. 434-438Konferensbidrag (Refereegranskat)
    Abstract [en]

    The use of NMR spectroscopy at high magnetic fields is a common tool in the analysis of lignin samples. In the presented study, NMR measurements on a group of softwood and hardwood kraft lignins at low field (1.0 T) with a benchtop NMR spectrometer, containing a permanent magnet, are investigated and evaluated. NMR based diffusion measurements were performed, for which the results were found to be fast, repeatable, and in good agreement numbers to measurements at high field. Measurements were also performed on a sample in alkaline solution, as a model for black liquor analysis, with promising initial results.

  • 20.
    Rönnols, Jerk
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Danieli, Ernesto
    Magritek GmbH, Germany.
    Freichels, Helene
    Magritek GmbH, Germany.
    Aldaeus, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Lignin analysis with benchtop NMR spectroscopy2019Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434XArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    Benchtop nuclear magnetic resonance (NMR) spectroscopy is an emerging field with an appealing profile for industrial applications. The instrumentation offers the possibility to measure NMR spectra in situations where high-field NMR spectroscopy is considered too expensive or complicated. In this study, we investigated the scope and limitations of 1H NMR measurements on kraft lignins and black liquors at low magnetic field strengths (1.0 and 1.5 T). The ability to quantify different classes of compounds was investigated and found to be promising. NMR-based diffusion measurements were performed, with the aim of gaining insight into the molar mass of the lignins at hand. These measurements were fast, repeatable and in good agreement with established methods.

  • 21.
    Rönnols, Jerk
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi.
    Jacobs, Anna
    RISE - Research Institutes of Sweden, Bioekonomi.
    Aldaeus, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi.
    Consecutive determination of softwood kraft lignin structure and molar mass from NMR measurements2017Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 71, nr 7-8, s. 563-570Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The general molecular properties and in particular, the molar mass of lignin are of central importance for industrial applications, as these data govern important thermal and mechanical characteristics. The focus of the present paper is pulsed field gradient-nuclear magnetic resonance (PFG-NMR), which is suitable for determination of lignins’ weight-Average molar mass, based on diffusion constants. The method is calibrated by lignin fractions characterized by matrix-Assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). It could be demonstrated on a set of softwood kraft lignins that the PFG-NMR approach gives results in very good agreement with those obtained using conventional size exclusion chromatography (SEC).

  • 22.
    Rönnols, Jerk
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Jacobs, Anna
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Aldaeus, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Recent advances in NMR spectroscopy of lignin and black liquor2018Ingår i: 15th European workshop on lignocellulosics and pulp: proceedings for oral presentations, 2018, s. 57-60Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This paper describes improvements in the methodology for NMR spectroscopic analysis of dissolved kraft lignins and black liquors, for structural analysis as well as for reaction monitoring. The described methodologies are variations and applications of non-uniform sampling (NUS) in 2D spectra and diffusion ordered spectroscopy (DOSY), with reduced experiment time and/or increased resolution and novel ways to track reactions through monitoring of diffusion of a reactant mixture.

  • 23.
    Rönnols, Jerk
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Jacobs, Anna
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Aldaeus, Fredrik
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Larsson, Tomas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Digging in the structure and functionality of lignocellulosic raw material: from academic knowledge towards industrial applications2018Ingår i: The 8th Nordic Wood Biorefinery Conference: NWBC 2018 : proceedings / [ed] Hytönen Eemeli, Vepsäläinen Jessica, Espoo: VTT , 2018, s. 205-205Konferensbidrag (Övrigt vetenskapligt)
  • 24.
    Rönnols, Jerk
    et al.
    RISE., Innventia.
    Larsson, Karolina
    RISE., Innventia.
    Jacobs, Anna
    RISE., Innventia.
    Aldaeus, Fredrik
    RISE., Innventia.
    Absolute determination of softwood kraft lignin molar mass using MALDI-TOF mass spectrometry and pulsed field gradient NMR2016Ingår i: 14th European Workshop on Lignocellulosics and Pulp: EWLP 2016, 2016, s. 143-146Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Knowledge of the molecular properties, e.g. the molar mass, of lignin are of central importance for industrial applications, since thermal and mechanical characteristics are governed by these. Here, a method for absolute determination of weight-average molar mass of kraft lignin, based on diffusion constants gained from PFG-NMR calibrated with lignin fractions characterized by MALDI-TOF-MS, is presented. The NMR method is compared to polystyrene calibration, and size exclusion chromatography with tetrahydrofuran as mobile phase.

  • 25.
    Rönnols, Jerk
    et al.
    RISE., Innventia.
    Schweinebarth, Hannah
    RISE., Innventia.
    Jacobs, Anna
    RISE., Innventia.
    Stevanic Srndovic, Jasna
    RISE., Innventia.
    Olsson, Anne-Mari
    RISE., Innventia.
    Reimann, Anders
    RISE., Innventia.
    Aldaeus, Fredrik
    RISE., Innventia.
    Structural changes in softwood kraft lignin during nonoxidative thermal treatment2015Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 30, nr 4, s. 550-561Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Heat treatment is a promising pre-processing method in the conversion of kraft lignins to carbon fibers. In this study, a kraft lignin was subjected to heat treatment at different lengths of time and at different temperatures. The molecular structure of the untreated and four heat treated lignins were investigated mainly by a variety of nuclear magnetic resonance spectroscopy (NMR) methods. The results were compared to structural information obtained by pyrolysis-gas chromatography-/mass spectrometry (py-GC/MS) and Fourier transform infrared spectroscopy (FTIR). It was observed that during the thermal treatment, the amount of β-O-4 ether moieties decreased, and an intramolecular conversion of secoisolariciresinol residues to cyclic ethers occurred. The effects on shape and size of the lignins were investigated by size exclusion chromatography (SEC) and NMR-diffusion measurements, by which the hydrodynamic radii were found to increase as a result of thermal treatment. It is discussed whether this depends on reduced flexibility and/or increased molar mass. In addition, the trends from the SEC and NMR analyses were compared to changes in glass transition temperature as determined by differential scanning calorimetry (DSC).

  • 26.
    Rönnols, Jerk
    et al.
    RISE., Innventia.
    Schweinebarth, Hannah
    RISE., Innventia.
    Jacobs, Anna
    RISE., Innventia.
    Stevanic Srndovic, Jasna
    RISE., Innventia.
    Olsson, Anne-Mari
    RISE., Innventia.
    Reimann, Anders
    RISE., Innventia.
    Aldaeus, Fredrik
    RISE., Innventia.
    Structural changes in softwood kraft lignin during thermal treatment2015Ingår i: 18th International Symposium on Wood, Fiber and Pulping Chemistry: 18th ISWFPC, 2015, Vol. 2, s. 366-369Konferensbidrag (Övrigt vetenskapligt)
  • 27.
    Sjöholm, Elisabeth
    et al.
    RISE., Innventia.
    Aldaeus, Fredrik
    RISE., Innventia.
    Reimann, Anders
    RISE., Innventia.
    Ropponen, Jarmo
    Talja, Riku
    Determination of fundamental thermal characteristics of lignin: a comparative study2014Konferensbidrag (Refereegranskat)
1 - 27 av 27
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