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  • 1.
    Abitbol, Tiffany
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Impact of surface charge on CNC phase separation and rheology2017Ingår i: International Conference on Nanotechnology for Renewable Materials 2017, TAPPI Press , 2017, s. 64-71Konferensbidrag (Refereegranskat)
  • 2.
    Abitbol, Tiffany
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Ahniyaz, Anwar
    RISE - Research Institutes of Sweden, Biovetenskap och material, Yta, process och formulering.
    Swerin, Agne
    RISE - Research Institutes of Sweden, Biovetenskap och material, Yta, process och formulering.
    UV-blocking hybrid nanocellulose films containing ceria and silica nanoparticles2018Ingår i: International Conference on Nanotechnology for Renewable Materials 2018, 2018, s. 503-515Konferensbidrag (Refereegranskat)
  • 3.
    Almhöjd, Ulrika S.
    et al.
    Sahlgrenska Academy, Sweden.
    Lingström, Peter
    Sahlgrenska Academy, Sweden.
    Nilsson, Åke
    Sahlgrenska Academy, Sweden.
    Noren, Jörgen G.
    Sahlgrenska Academy, Sweden.
    Siljeström, Silje
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    ֖stlund, Å.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Bernin, D.
    University of Gothenburg, Sweden.
    Molecular Insights into Covalently Stained Carious Dentine Using Solid-State NMR and ToF-SIMS2017Ingår i: Caries Research, ISSN 0008-6568, E-ISSN 1421-976X, Vol. 51, nr 3, s. 255-263Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dyes currently used to stain carious dentine have a limited capacity to discriminate normal dentine from carious dentine, which may result in overexcavation. Consequently, finding a selective dye is still a challenge. However, there is evidence that hydrazine-based dyes, via covalent bonds to functional groups, bind specifically to carious dentine. The aim of this study was to investigate the possible formation of covalent bonds between carious dentine and 15N2-hydrazine and the hydrazine-based dye, 15N2-labelled Lucifer Yellow, respectively. Powdered dentine from extracted carious and normal teeth was exposed to the dyes, and the staining reactions were analysed using time-of-flight secondary ion mass spectrometry (ToF-SIMS), solid-state 13C-labelled nuclear magnetic resonance (NMR) and 15N-NMR spectroscopy. The results showed that 15N2-hydrazine and 15N2-labelled Lucifer Yellow both bind to carious dentine but not to normal dentine. It can thus be concluded that hydrazine-based dyes can be used to stain carious dentine and leave normal dentine unstained.

  • 4.
    Andersson, Sofia
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Bengtsson, Andreas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. KTH Royal institute of technology, Sweden.
    Åkerström, Mårten
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Sedin, Maria
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sjöholm, Elisabeth
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    The impact of inorganic elements on lignin‐based carbon fibre quality2018Ingår i: 15th European workshop on lignocelllulosics and pulp: Proceedings for poster presentations, 2018, s. 119-122Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The influence of inorganic elements on lignin ‐based carbon fibre (CF) quality was studied using sulphates of Na +, K+, Mg2+, Fe2+, Al3+. The metal sulphates were added to wet spun prefibres made from softwood kraft lignin (SKL):cellulose (70:30) and melt spun prefibres made from low molecular mass SKL. An increase in concentration from 0.1 w% to about 0.4 w% did neither affect the mechanical properties nor the morphology as observed by SEM. In contrast, metal sulphates added to the initial 0.45 w% to a total range 1.5 to 5.0 w%, was found detrimental to the melt spinning and to the final CF quality. Thus, the recommendation of <0.1 w% ash in kraft lignin may be exceeded, but more research is needed to establish the upper concentration limit.

  • 5.
    Anheden, Marie
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Kulander, Ida
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Pettersson, Karin
    Wallinder, Johan
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Vamling, Lennart
    Chalmers University of Technology, Sweden.
    Hjerpe, Carl Johan
    F Industri, Sweden.
    Fugelsang, Malin
    F Industri, Sweden.
    Håkansson, Åsa
    Preem, Sweden.
    Evaluation of alternative routes for production of bio-oil from forest residues and kraft lignin2018Ingår i: The 8th Nordic Wood Biorefinery Conference: NWBC 2018 : proceedings / [ed] Hytönen Eemeli, Vepsäläinen Jessica, Espoo: VTT , 2018, s. 85-89Konferensbidrag (Refereegranskat)
  • 6.
    Bach-Oller, Albert
    et al.
    Luleå University of Technology, Sweden.
    Furusjö, Erik
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Umeki, Kentaro
    Luleå University of Technology, Sweden.
    Effect of potassium impregnation on the emission of tar and soot from biomass gasification2019Ingår i: Energy Procedia, Elsevier, 2019, Vol. 1458, s. 619-624Konferensbidrag (Refereegranskat)
    Abstract [en]

    Entrained flow gasification of biomass has the potential to generate synthesis gas as a source of renewable chemicals, electricity, and heat. Nonetheless, formation of tar and soot is a major challenge for continuous operation due to the problems they cause at downstream of the gasifier. Our previous studies showed the addition of alkali in the fuel can bring significant suppression of such undesirable products.

    The present work investigated, in a drop tube furnace, the effect of potassium on tar and soot formation (as well as on its intermediates) for three different types of fuels: an ash lean stemwood, a calcium rich bark and a silicon rich straw. The study focused on an optimal method for impregnating the biomass with potassium. Experiments were conducted for different impregnation methods; wet impregnation, spray impregnation, and solid mixing to investigate different levels of contact between the fuel and the potassium.

    Potassium was shown to catalyze both homogenous and heterogeneous reactions. Wet and spray impregnation had similar effects on heterogeneous reactions (in char conversion) indicating that there was an efficient molecular contact between the potassium and the organic matrix even if potassium was in the form of precipitated salts at a micrometer scale. On the other hand, potassium in the gas phase led to much lower yields of C2 hydrocarbons, heavy tars and soot. These results revealed that potassium shifted the pathways related to tar and soot formation, reducing the likelihood of carbon to end up as soot and heavy tars by favouring the formation of lighter compounds such as benzene. A moderate interaction between the added potassium and the inherent ash forming elements were also observed: Potassium had a smaller effect when the fuel was naturally rich in silicon.

    The combined results open the door to a gasification process that incorporates recirculation of naturally occurring potassium to improve entrained flow gasification of biomass.

  • 7.
    Bach-Oller, Albert
    et al.
    Luleå University of Technology, Sweden.
    Furusjö, Erik
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. Luleå University of Technology, Sweden.
    Umeki, Kentaro
    Luleå University of Technology, Sweden.
    On the role of potassium as a tar and soot inhibitor in biomass gasification2019Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 254, artikel-id 113488Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The work investigates in a drop tube furnace the effect of potassium on carbon conversion for three different types of fuels: an ash lean stemwood, a calcium-rich bark and a silicon-rich straw. The study focuses on an optimal method for impregnating the biomass with potassium. The experiments are conducted for 3 different impregnation methods; wet impregnation, spray impregnation, and dry mixing to investigate different levels of contact between the fuel and the potassium. Potassium is found to catalyse both homogenous and heterogeneous reactions. All the impregnation methods showed a significant effect of potassium on heterogeneous reactions (char conversion). The fact that dry mixing of potassium in the biomass shows an effect reveals the existence of a gas-induced mechanism that supply and distributes potassium on the char particles. Concerning the effect of potassium on homogenous reactions, it is found that potassium in the gas phase leads to much lower yields of C2 hydrocarbons, heavy tars and soot. The results indicate that potassium reduces the likelihood of light aromatic to progress toward heavier polyaromatic hydrocarbons clusters, thereby inhibiting the formation of soot-like material. A moderate interaction between the added potassium and the inherent ash forming elements is also observed: Potassium has a smaller effect when the fuel is naturally rich in silicon. The combined results are of interest for the design of a gasification process that incorporates recirculation of naturally occurring potassium to improve entrained flow gasification of biomass. 

  • 8.
    Baker, Darren A
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Sedin, Maria
    Södra skogsägarna ekonomisk förening, Sweden.
    Landmer, Alice
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Friman, Linda
    Södra skogsägarna ekonomisk förening, Sweden.
    Echardt, Linda
    Södra skogsägarna ekonomisk förening, Sweden.
    Structural carbon fibre from kraft lignin2017Ingår i: The 7th Nordic Wood Biorefinery Conference held in Stockholm, Sweden, 28-30 Mar. 2017: NWBC 2017, Stockholm: RISE Bioekonomi , 2017, s. 65-67Konferensbidrag (Refereegranskat)
    Abstract [en]

    The GreenLight consortium is working to demonstrate a biobased, renewable and economically viable carbon fibre from lignin. The aim is to provide a basis for commercial production of lignin, lignin filaments, carbon fibre and carbon fibre composites. The most difficult boundary to success in the developing lignin as a precursor for continuous filament carbon fibre has been identified as melt extrusion of lignin. The consortium is working to develop a robust melt spinning platform for use up to the 1,000 filament scale. Methodical studies have been performed to examine lignin separation from differing black liquors derived from both softwood and hardwood and assess their viability in terms of thermal, compositional and structural properties. The move will then be made to pilot scale melt spinning at the 100 filament scale. The characteristics of some kraft lignin fractions obtained from the same Sodra Monsteras softwood kraft black liquor have been studied. The lignins were manufactured in quantities of approximately 10-20kg. Several variations of the LignoBoost process were used to provide lignins with improved melt spinning properties. The lignins were of high purity, each having low carbohydrate, extractives and inorganic contents. All four lignins could be melt spun and converted to carbon fibre.

  • 9.
    Balakshin, Mikhail
    et al.
    Aalto University, Finland.
    Capanema, Ewellyn A
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Huang, Zeen
    FP Innovations, Cananda.
    Sulaeva, Irina
    BOKU, Austria.
    Rojas, Orlando
    Aalto University, Finland.
    Feng, Martin
    FP Innovations, Canada.
    Rosenau, Thomas
    BOKU, Austria.
    Potthast, Antje
    BOKU, Austria.
    Recent achievement in the valorization of technical lignins2018Ingår i: The 8th Nordic Wood Biorefinery Conference: NWBC 2018 : proceedings / [ed] Hytönen Eemeli, Vepsäläinen Jessica, Espoo, 2018, s. 151-156Konferensbidrag (Refereegranskat)
  • 10.
    Belaineh, Dagmawi
    et al.
    Linköping University, Sweden.
    Andreasen, Jens W
    DTU Technical University of Denmark, Denmark.
    Palisaitis, Justinas
    Linköping University, Sweden.
    Malti, Abdellah
    KTH Royal institute of Technology, Sweden.
    Håkansson, Karl
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Wågberg, Lars
    KTH Royal institute of Technology, Sweden.
    Crispin, Xavier
    Linköping university, Sweden.
    Engquist, Isak
    Linköping university, Sweden.
    Berggren, Magnus
    Linköping university, Sweden.
    Controlling the Organization of PEDOT:PSS on Cellulose Structures2019Ingår i: ACS Applied Polymer Materials, Vol. 1, nr 9, s. 2342-2351Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Composites of biopolymers and conducting polymers are emerging as promising candidates for a green technological future and areactively being explored in various applications, such as in energy storage ,bioelectronics, and thermoelectrics. While the device characteristics of these composites have been actively investigated, there is limited knowledge concerning the fundamental intracomponent interactions and the modes of molecular structuring. Here, by use of cellulose and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), it is shown that the chemical and structural makeup of the surfaces of the composite components are critical factors that determine the materials organization at relevant dimensions. AFM, TEM, and GIWAXS measurements show that when mixedwith cellulose nanofibrils, PEDOT:PSS organizes into continuous nanosized beadlike structures with an average diameter of 13 nm on the nanofibrils. In contrast, when PEDOT:PSS is blended with molecular cellulose, a phase-segregated conducting network morphology is reached, with a distinctly relatively lower electric conductivity. These results provide insight into the mechanisms ofPEDOT:PSS crystallization and may have significant implications for the design of conducting biopolymer composites for a vast array of applications.

  • 11.
    Bengtsson, Andreas
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. KTH Royal institute of technology, Sweden.
    Sjöholm, Elisabeth
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    Conditions for the stabilisation of lignin-cellulose prefibres for carbon fibre production2018Ingår i: 15th European workshop on lignocellulosics and pulp: Proceedings for poster presentations, 2018, s. 111-114Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Stabilisation of the prefibre is a time-consuming step in carbon fibre (CF) production. In this paper the stabilisation condition of dry-jet wet-spun lignin-cellulose (LC) prefibres (70:30  t%) are reported. The impact of prefibre-impregnation by ammonium dihydrogen phosphate (ADHP) and various thermal conditions were evaluated by measuring the yield and mechanical properties of the final CFs. The addition of ADHP improved the CF yields from 32-40 wt% to 45-47 wt% but had a slight negative impact on the tensile modulus (TM) whereas no significant difference in tensile strength (TS) was observed. The absence of fibre fusion and glass transition temperature (Tg) indicate successful stabilisation of all prefibres. This implies possibilities of using short stabilisation times of LC prefibres in CF production.

  • 12.
    Borrega, Marc
    et al.
    Aalto university, Finland ; VTT Technical Research Centre of Finland Ltd, Finland.
    Larsson, Per Tomas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Ahvenainen, Patrik
    University of Helsinki, Finland.
    Ceccherini, Sara
    Aalto university, Finland.
    Maloney, Thaddeus
    Aalto university, Finland.
    Rautkari, Lauri
    Aalto university, Finland.
    Sixta, Herbert
    Aalto university, Finland.
    Birch wood pre-hydrolysis vs pulp post-hydrolysis for the production of xylan-based compounds and cellulose for viscose application2018Ingår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 190, s. 212-221Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hydrothermal treatments of birch wood and kraft pulp were compared for their ability to extract the xylan and produce viscose-grade pulp. Water post-hydrolysis of kraft pulp produced a high-purity cellulosic pulp with lower viscosity but higher cellulose yield than traditional pre-hydrolysis kraft pulping of wood. Post-hydrolysis of pulp also increased the crystallite dimensions and degree of crystallinity in cellulose, and promoted a higher extent of fibril aggregation. The lower specific surface area in post-hydrolyzed pulps, derived from their larger fibril aggregates, decreased the accessibility of –OH groups. However, this lower accessibility did not seem to decrease the pulp reactivity to derivatizing chemicals. In the aqueous side-stream, the xylose yield was similar in both pre- and post-hydrolysates, although conducting post-hydrolysis of pulp in a flow-through system enabled the recovery of high purity and molar mass (∌10 kDa) xylan for high-value applications.

  • 13.
    Brunklaus, Birgit
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Molnar, Stefan
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Sandin, Gustav
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Torén, Johan
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Mangold, Mikael
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Choice of social indicators within technology development – the case of mobile biorefineries in Europe2018Ingår i: Social LCA: People and Places for Partnership, 2018, s. 162-166Konferensbidrag (Övrigt vetenskapligt)
  • 14.
    Brännvall, Elisabet
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Increasing pulp yield in kraft cooking of softwoods by high initial effective alkali concentration (HIEAC) during impregnation leading to decreasing secondary peeling of cellulose2018Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 72, nr 10, s. 819-827Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pulp yield can be improved by a more homogeneous delignification of the chips, achieved by improved impregnation prior to the cooking stage. Complete and efficient impregnation is obtained by increasing the diffusion rate by means of an impregnation liquor with a high initial effective alkali concentration (HIEAC). In the present study, the effect of HIEAC in the impregnation was evaluated and compared to a reference impregnation procedure and a prolonged impregnation. After the various impregnation scenarios, the alkali concentration was always adjusted to the same level in the beginning of the cooking stage. Impregnation with a HIEAC resulted in yield improvements by 1-1.5% units, due to a higher cellulose yield and possibly also to higher yield of glucomannan. The HIEAC with an even alkali distribution within the chips prior to the cooking stage resulted in a more uniform delignification carbohydrate degradation. Yield increase obtained by uniform delignification is due to both decreased shives content as well as less secondary peeling.

  • 15.
    Brännvall, Elisabet
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Kulander, Ida
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Consequences in a softwood kraft pulp mill of initial high alkali concentration in the impregnation stage2019Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 34, nr 1, s. 28-35Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Impregnation with high initial concentration is fast and efficient, leading to a homogeneous delignification in the subsequent cook, resulting in improved screened pulp yield. To obtain high initial alkali concentration, the white liquor flow needs to be significantly increased. The moisture content of the wood chips and the alkali concentration of the white liquor limit the initial alkali concentration of the impregnation liquor that can be reached. It is therefore of interest to evaluate the possibility to implement high alkali impregnation (HAI) industrially and the consequences this would have on the mill system. The effect of HAI on mass and energy balances in a kraft pulp mill has been studied using mill model simulations. The sensitivity to disturbances in important parameters for process control has been compared to impregnation scenarios used industrially. It was shown that high initial alkali concentration can be achieved on industrial scale by increased white liquor flow. HAI has a positive effect on recovery flows and reduces the need for make-up chemicals. The HAI concept is less sensitive to variations in process parameters, such as chip moisture and white liquor concentration, thus diminishing the risk of alkali depletion in chip cores. © 2019 Brännvall and Kulander.

  • 16.
    Brännvall, Elisabet
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Reimann, Anders
    RISE - Research Institutes of Sweden, Bioekonomi, Biobaserade material.
    The balance between alkali diffusion and alkali consuming reactions during impregnation of softwood. Impregnation for kraft pulping revisited2018Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 72, nr 3, s. 169-178Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of the impregnation stage is to ensure that cooking chemicals reach all parts of the chips. However, as alkali comes into contact with wood, reactions take place, which alter the paths available for ionic transport and dissolve wood components. The aim of the present study is to establish the most favorable impregnation conditions, which result in an even alkali concentration profile through the chip at a sufficiently high level without extensive yield losses due to peeling. Softwood chips were subjected to different impregnation conditions. The progress of impregnation was assessed by analyzing the concentration of hydroxide ions in the bound liquor inside wood chips and the release of acetic acid. The extent of undesired reactions was measured as the amount of carbohydrate degradation products formed and amount of wood dissolved. Increased temperature and time lead to more degradation of the carbohydrates during impregnation. At high temperature, the concentration of alkali in the bound liquor was lower due to higher alkali consumption in degradation reactions. The most favorable process is to perform impregnation at an elevated initial effective alkali (EA) for a short time. This resulted in an increased alkali concentration in the bound liquor within the chip without extensive carbohydrate degradation.

  • 17.
    Carlmark, Anna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    A polymeric coat for nanodroplets2019Ingår i: Nature Nanotechnology, ISSN 1748-3387, E-ISSN 1748-3395, Vol. 14, s. 640-641Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Grafting nanodroplets by surface-initiated atom transfer radical polymerization can be carried out at liquid–liquid interfaces.

  • 18.
    Carlmark, Anna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Modification of nanocellulose with tailored latex nanoparticles2018Ingår i: Recent advances in cellulose nanotechnology research: production, characterization and applications, Trondheim: RISE PFI , 2018Konferensbidrag (Övrigt vetenskapligt)
  • 19.
    Carvalho, Lara
    et al.
    Luleå University of Technology, Sweden.
    Lundgren, Joakim
    Luleå University of Technology, Sweden;IIASA International Institute for Applied Systems Analysis, Austria.
    Wetterlund, Elisabeth
    Luleå University of Technology, Sweden;IIASA International Institute for Applied Systems Analysis, Austria.
    Wolf, Jens
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Furusjö, Erik
    Luleå University of Technology, Sweden; IVL Swedish Environmental Institute, Sweden.
    Methanol production via black liquor co-gasification with expanded raw material base – Techno-economic assessment2018Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 225, s. 570-584Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Entrained flow gasification of black liquor combined with downstream-gas-derived synthesis of biofuels in Kraft pulp mills has shown advantages regarding energy efficiency and economic performance when compared to combustion in a recovery boiler. To further increase the operation flexibility and the profitability of the biofuel plant while at the same time increase biofuel production, black liquor can be co-gasified with a secondary feedstock (blend-in feedstock). This work has evaluated the prospects of producing biofuels via co-gasification of black liquor and different blend-in feedstocks (crude glycerol, fermentation residues, pyrolysis liquids) at different blend ratios. Process modelling tools were used, in combination with techno-economic assessment methods. Two methanol grades, crude and grade AA methanol, were investigated. The results showed that the co-gasification concepts resulted in significant increases in methanol production volumes, as well as in improved conversion efficiencies, when compared with black liquor gasification; 5–11 and 4–10 percentage point in terms of cold gas efficiency and methanol conversion efficiency, respectively. The economic analysis showed that required methanol selling prices ranging from 55 to 101 €/MWh for crude methanol and 58–104 €/MWh for grade AA methanol were obtained for an IRR of 15%. Blend-in led to positive economies-of-scale effects and subsequently decreased required methanol selling prices, in particular for low cost blend-in feedstocks (prices below approximately 20 €/MWh). The co-gasification concepts showed economic competitiveness to other biofuel production routes. When compared with fossil fuels, the resulting crude methanol selling prices were above maritime gas oil prices. Nonetheless, for fossil derived methanol prices higher than 80 €/MWh, crude methanol from co-gasification could be an economically competitive option. Grade AA methanol could also compete with taxed gasoline. Crude glycerol turned out as the most attractive blend-in feedstock, from an economic perspective. When mixed with black liquor in a ratio of 50/50, grade AA methanol could even be cost competitive with untaxed gasoline.

  • 20.
    de la Motte, Hanna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Circular recycling of cotton fibers recovered from polyester/cotton textile blends2018Konferensbidrag (Övrigt vetenskapligt)
  • 21.
    de la Motte, Hanna
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Palme, Anna
    Chalmers University of Technology, Sweden.
    The development of the Blend Re:windprocess2018Rapport (Övrigt vetenskapligt)
  • 22.
    Englund, Finn
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Wedin, Helena
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Ribul, Miriam
    London Doctoral Design Centre (LDoC), UK.
    de la Motte, Hanna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Östlund, Åsa
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Textile tagging to enable automated sorting and beyond: a report to facilitate an active dialogue within the circular textile industry2018Rapport (Övrigt vetenskapligt)
  • 23.
    Fall, Andreas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Nanocellulose and graphene: promising hybrid materials2018Ingår i: Recent advances in cellulose nanotechnology research: production, characterization and applications, Trondheim: RISE PFI , 2018Konferensbidrag (Refereegranskat)
  • 24.
    Frishammar, Johan
    et al.
    Luleå University of Technology, Sweden.
    Söderholm, Patrik
    Luleå University of Technology, Sweden.
    Hellsmark, Hans
    Chalmers University of Technology, Sweden.
    Mossberg, Johanna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    A Knowledge-based Perspective on System Weaknesses in Technological Innovation Systems2019Ingår i: Science and Public Policy, ISSN 0302-3427, E-ISSN 1471-5430, Vol. 46, nr 1, s. 55-70Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The literature on technological innovation systems (TIS) provides policymakers and other actors with a scheme of analysis to identify system weaknesses. In doing so, TIS analysis centres on which system weaknesses policy interventions should target to promote further development of a particular system. However, prior TIS literature has not sufficiently elaborated on what may constitute the conceptual roots of a ‘weakness’. We apply a knowledge-based perspective and propose that many—albeit not all—system weaknesses may root in four types of knowledge problems: uncertainty, complexity, equivocality, and ambiguity. Employing these as sensitizing concepts, we study system weaknesses by analysing data from a biorefinery TIS in Sweden. This analysis results in novel implications for the TIS literature and for achieving a better match between system weaknesses and the design of innovation policies.

  • 25.
    Furusjö, Erik
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. IVL Swedish Environmental Institute, Sweden.
    Ma, Chunyan
    Luleå University of Technology, Sweden.
    Ji, Xiaoyan
    Luleå University of Technology, Sweden.
    Carvalho, Lara
    Luleå University of Technology, Sweden.
    Lundgren, Joakim
    Luleå University of Technology, Sweden.
    Wetterlund, Elisabeth
    Luleå University of Technology, Sweden.
    Alkali enhanced biomass gasification with in situ S capture and novel syngas cleaning. Part 1: Gasifier performance2018Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 157, s. 96-105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Previous research shows that alkali addition in entrained flow biomass gasification can increase char conversion and decrease tar and soot formation through catalysis. This paper investigates two other potential benefits of alkali addition: increased slag flowability and in situ sulfur capture. Thermodynamic equilibrium calculations show that addition of 2–8% alkali catalyst to biomass completely changes the chemical domain of the gasifier slag phase to an alkali carbonate melt with low viscosity. This can increase feedstock flexibility and improve the operability of an entrained flow biomass gasification process. The alkali carbonate melt also leads to up to 90% sulfur capture through the formation of alkali sulfides. The resulting reduced syngas sulfur content can potentially simplify gas cleaning required for catalytic biofuel production. Alkali catalyst recovery and recycling is a precondition for the economic feasibility of the proposed process and is effected through a wet quench. It is shown that the addition of Zn for sulfur precipitation in the alkali recovery loop enables the separation of S, Ca and Mg from the recycle. For high Si and Cl biomass feedstocks, an alternative separation technology for these elements may be required to avoid build-up.

  • 26.
    Gao, Yu
    et al.
    Washington University, USA.
    Walker, Michael J
    Washington University, USA.
    Barrett, Jacob A
    University of California, USA.
    Hosseinaei, Omid
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Harper, David P
    University of Tennessee, USA.
    Ford, Peter C
    University of California, USA.
    Williams, Brent J
    Washington University, USA.
    Foston, Marcus B
    Washington University, USA.
    Analysis of gas chromatography/mass spectrometry data for catalytic lignin depolymerization using positive matrix factorization2018Ingår i: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 20, nr 18, s. 4366-4377Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Various catalytic technologies are being developed to efficiently convert lignin into renewable chemicals. However, due to its complexity, catalytic lignin depolymerization often generates a wide and complex distribution of product compounds. Gas chromatography/mass spectrometry (GC-MS) is a common analytical technique to profile the compounds that comprise lignin depolymerization products. GC-MS is applied not only to determine the product composition, but also to develop an understanding of the catalytic reaction pathways and of the relationships among catalyst structure, reaction conditions, and the resulting compounds generated. Although a very useful tool, the analysis of lignin depolymerization products with GC-MS is limited by the quality and scope of the available mass spectral libraries and the ability to correlate changes in GC-MS chromatograms to changes in lignin structure, catalyst structure, and other reaction conditions. In this study, the GC-MS data of the depolymerization products generated from organosolv hybrid poplar lignin using a copper-doped porous metal oxide catalyst and a methanol/dimethyl carbonate co-solvent was analyzed by applying a factor analysis technique, positive matrix factorization (PMF). Several different solutions for the PMF model were explored. A 13-factor solution sufficiently explains the chemical changes occurring to lignin depolymerization products as a function of lignin, reaction time, catalyst, and solvent. Overall, seven factors were found to represent aromatic compounds, while one factor was defined by aliphatic compounds.

  • 27.
    Giummarella, Nicola
    et al.
    KTH Royal Institute of Technology, Sweden.
    Henriksson, Gunnar
    KTH Royal Institute of Technology, Sweden.
    Salmen, Lennart
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Lawoko, Martin
    KTH Royal Institute of Technology, Sweden.
    On the effect of hemicellulose removal on cellulose-lignin interactions2017Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 32, nr 4, s. 542-549Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In a recent study, it was suggested that there could be direct associations between cellulose and lignin in mild alkaline cooked pulps. The observation was based on studies showing that the molecular straining of lignin was similar to that of cellulose. This finding has serious ramifications for technical production of pulps as it could expand on what is known about recalcitrant lignin removal during pulping. Herein, we investigate the possible interaction between cellulose and lignin discussing possible mechanisms involved at the nano- and molecular-scales, and present support for that the removal of hemicellulose by hot water extraction or mild kraft pulping causes strong interactions between lignin and cellulose. 

  • 28.
    Goldsworthy, Kate
    et al.
    University of the Arts London, UK.
    Roos, Sandra
    RISE - Research Institutes of Sweden, Material och produktion.
    Sandin, Gustav
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Peters, Greg
    Chalmers University of Technology, Sweden.
    Towards a Quantified Design Process: Bridging Design and Life Cycle Assessment2016Ingår i: Circular Transitions Proceedings, 2016, s. 208-221Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In this paper we describe how design researchers and environmental researchers are making a joint effort in overcoming the disciplinary barriers for collaboration. By comparing existing processes and identifying potential opportunities arising from inter-disciplinary collaboration the aim is to propose methods for building a bridge between disciplines. A model for “quantified design” is generated, and explored, relevant for designers, design researchers as well as LCA researchers.

  • 29.
    Granberg, Hjalmar
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Sandberg, Mats
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Håkansson, Karl
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Pilot scale production of interactive zinc oxide paper and its multiple applicability2019Ingår i: PaperCon 2019: Proceedings, TAPPI Press, 2019, artikel-id PF3.3Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    A study has been made of the production of zinc oxide (ZnO) paper in a pilot paper machine. Bleached sulphate softwood pulp (70%) and bleached sulphate hardwood pulp (30%) were corefined. Cationic polyacrylamide (CPAM) was used as retention agent, while alkyl ketene dimer (AKD) was used as sizing agent for some samples. Some papers were screen printed with a conducting carbon-based ink to produce a photosensor device. Two methods were used to study the photocatalysis: immersing ZnO papers into kongo red dispersions or resazurin (Rz) based photocatalyst activity indicator ink and exposing the papers to ultraviolet (UV) light in a sunlight simulator. ZnO papers of approximately 60gsm were successfully produced on the pilot scale machine, which was run at a low speed (100m/min) and the retention of ZnO particles was good in all samples. The paper looked like an ordinary white printing paper product, but was a truly interactive material, exhibiting photoconductivity and enabling use as an excellent photosensor.

  • 30.
    Guccini, Valentina
    et al.
    Stockholm University, Sweden; Wallenberg Wood Science Center, Sweden.
    Yu, Shun
    RISE - Research Institutes of Sweden, Bioekonomi. Stockholm University, Sweden; Wallenberg Wood Science Center, Sweden.
    Agthe, Michael
    Stockholm University, Sweden; University of Hamburg, Germany.
    Gordeyeva, Korneliya S.
    Stockholm University, Sweden.
    Trushkina, Yulia
    Stockholm University, Sweden.
    Fall, Andreas B.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. Stockholm University, Sweden.
    Schütz, Christina
    Stockholm University, Sweden; Wallenberg Wood Science Center, Sweden; University of Luxembourg, Luxembourg.
    Salazar-Alvarez, German
    Stockholm University, Sweden; Wallenberg Wood Science Center, Sweden.
    Inducing nematic ordering of cellulose nanofibers using osmotic dehydration2018Ingår i: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 10, nr 48, s. 23157-23163Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The formation of nematically-ordered cellulose nanofiber (CNF) suspensions with an order parameter fmax ≈ 0.8 is studied by polarized optical microscopy, small-angle X-ray scattering (SAXS), and rheological measurements as a function of CNF concentration. The wide range of CNF concentrations, from 0.5 wt% to 4.9 wt%, is obtained using osmotic dehydration. The rheological measurements show a strong entangled network over all the concentration range whereas SAXS measurements indicate that at concentrations &gt;1.05 wt% the CNF suspension crosses an isotropic-anisotropic transition that is accompanied by a dramatic increase of the optical birefringence. The resulting nanostructures are modelled as mass fractal structures that converge into co-existing nematically-ordered regions and network-like regions where the correlation distances decrease with concentration. The use of rapid, upscalable osmotic dehydration is an effective method to increase the concentration of CNF suspensions while partly circumventing the gel/glass formation. The facile formation of highly ordered fibers can result in materials with interesting macroscopic properties.

  • 31.
    Gunnarsson, Maria
    et al.
    Chalmers University of technology, Sweden.
    Bernin, Diana
    Chalmers University of technology, Sweden.
    Östlund, Åsa
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Hasani, Merima
    Chalmers University of technology, Sweden.
    CO2 capturing and the influence on cellulose dissolution in the NaOH(aq) system2018Ingår i: 15th European workshop on lignocellulosics and pulp: Proceedings for poster presentations, 2018, s. 419-422Konferensbidrag (Refereegranskat)
    Abstract [en]

    The narrow dissolution window for cellulose in NaOH(aq) is a limiting factor in the production of regenerated cellulose materials, which is why understanding of the molecular interactions in this solvent system is of the highest importance. In this work, we highlight the interaction between cellulose and CO2 in NaOH(aq). The model compound methyl α-D-glycopyranoside (MeO-Glcp) was used to compare the difference of the dissolved state in NaCl(aq) and NaOH(aq), including both pre and post-dissolution addition of CO2. N MR a nd A TR-IR  spectroscopy as well as ocular observations were used in the evaluation.  1H and 13C NMR spectroscopy showed a clear change in chemical shift of the MeO-Glcp when dissolved in NaOH(aq) compared to NaCl(aq), which is a result of deprotonation. Interestingly, the addition of CO2 either pre or post-dissolution of MeO-Glcp in NaOH(aq) affected the chemical shifts differently (apart from the expected change in pH). With quantitative 13C NMR measurements, the uptake of CO2 was found to be more than twice as high when the CO2 was added post-dissolution of MeO-Glcp in NaOH(aq) compared to prior to dissolution. This suggests that specific interactions occur between CO2 and MeO-Glcp when the latter is dissolved prior to the addition of CO2, which could be attributed to the deprotonated state of MeO-Glcp. Furthermore, the dissolved state of cellulose in NaOH(aq) was visually shown to iffer in terms of pre or post-dissolution addition of CO2. Post-dissolution addition of CO2 resulted in the formation of a gelled structure when solutions was left to age in room temperature for two weeks. ATR-IR spectroscopy of materials regenerated from the aged solutions confirmed the introduction of a n ew waveband corresponding to CO2 out-of-phase stretching confirming the sorption of CO2 on cellulose when dissolved in NaOH(aq).

  • 32.
    Gunnarsson, Maria
    et al.
    Chalmers University of Technology, Sweden.
    Bernin, Diana
    University of Gothenburg, Sweden ; Chalmers University of Technology, Sweden.
    Östlund, Åsa
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Hasani, Merima
    Chalmers University of Technology, Sweden.
    The CO2 capturing ability of cellulose dissolved in NaOH(aq) at low temperature2018Ingår i: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 20, nr 14, s. 3279-3286Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Herein, we explore the intrinsic ability of cellulose dissolved in NaOH(aq) to reversibly capture CO2. The stability of cellulose solutions differed significantly when adding CO2 prior to or after the dissolution of cellulose. ATR-IR spectroscopy on cellulose regenerated from the solutions, using ethanol, revealed the formation of a new carbonate species likely to be cellulose carbonate. To elucidate the interaction of cellulose with CO2 at the molecular level, a 13C NMR spectrum was recorded on methyl α-d-glucopyranoside (MeO-Glcp), a model compound, dissolved in NaOH(aq), which showed a difference in chemical shift when CO2 was added prior to or after the dissolution of MeO-Glcp, without a change in pH. The uptake of CO2 was found to be more than twice as high when CO2 was added to a solution after the dissolution of MeO-Glcp. Altogether, a mechanism for the observed CO2 capture is proposed, involving the formation of an intermediate cellulose carbonate upon the reaction of a cellulose alkoxide with CO2. The intermediate was observed as a captured carbonate structure only in regenerated samples, while its corresponding NMR peak in solution was absent. The reason for this is plausibly a rather fast hydrolysis of the carbonate intermediate by water, leading to the formation of CO3 2-, and thus increased capture of CO2. The potential of using carbohydrates as CO2 capturing agents in NaOH(aq) is shown to be simple and resource-effective in terms of the capture and regeneration of CO2.

  • 33.
    Guo, Juan
    et al.
    Chinese Academy of Forestry, China.
    Zhou, Haibin
    Chinese Academy of Forestry, China.
    Stevanic Srndovic, Jasna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Dong, Mengyu
    Chinese Academy of Forestry, China.
    Yu, Min
    Chinese Academy of Forestry, China.
    Salmen, Lennart
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Yin, Yafang
    Chinese Academy of Forestry, China.
    Effects of ageing on the cell wall and its hygroscopicity of wood in ancient timber construction2018Ingår i: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 52, nr 1, s. 131-147Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An important traditional load bearing member in oriental ancient timber structure buildings, i.e. Huagong (flower arm), was selected to explore the alterations in cell wall components and hygroscopic properties of wood during long time ageing. This archaeological poplar (Populus spp.) wood with cal. BP 690: BP 790 was studied from the wood surface and inwards by means of imaging FTIR spectroscopy, X-ray diffraction and dynamic vapour sorption. The deterioration of the archaeological wood mainly displayed a depolymerization of glucomannan and lignin as well as a hydrolysis of the glucuronic acid of xylan and of the aromatic C–O groups in the condensed lignins or lignin–carbohydrate complexes. Furthermore, the degradation promoted the rearrangement of the cellulose molecules in adjacent microfibrils. The cellulose crystallites in the archaeological wood were therefore packed more tightly and had larger diameter. The structural alterations of wood cell wall components and a decrease in crystallinity contributed to an increase in the number of moisture bonding sites and led to an increase in both the equilibrium moisture content of the archaeological wood in the entire RH range as well as an increase in hysteresis.

  • 34.
    Guo, Zengwei
    et al.
    RISE - Research Institutes of Sweden, Material och produktion, IVF.
    Lindqvist, Karin
    RISE - Research Institutes of Sweden, Material och produktion, IVF.
    de la Motte, Hanna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    An efficient recycling process of glycolysis of PET in the presence of a sustainable nanocatalyst2018Ingår i: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 135, nr 21, artikel-id 46285Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We demonstrate that the catalyst Perkalite F100 efficiently works as a nanocatalyst in the depolymerization of poly(ethylene terephthalate) (PET). After depolymerization of PET in the presence of ethylene glycol and the Perkalite nanocatalyst, the main product obtained was bis(2-hydroxylethyl) terephthalate (BHET) with high purity, as confirmed by Fourier transform infrared spectroscopy and NMR. The BHET monomers could serve directly as starting materials in a further polymerization into PET with a virgin quality and contribute to a solution for the disposal of PET polymers. Compared with the direct glycolysis of PET, the addition of a predegradation step was shown to reduce the reaction time needed to reach the depolymerization equilibrium. The addition of the predegradation step also allowed lower reaction temperatures. Therefore, the strategy to include a predegradation step before depolymerization is suitable for increasing the efficiency of the glycolysis reaction of PET into BHET monomers.

  • 35.
    Göhl, Johan
    et al.
    Fraunhofer-Chalmers Centre, Sweden.
    Markstedt, Kajsa
    Wallenberg Wood Science Center, Sweden ; Chalmers University of Technology, Sweden.
    Mark, Andreas
    Fraunhofer-Chalmers Centre, Sweden.
    Håkansson, Karl
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. Wallenberg Wood Science Center, Sweden ; Chalmers University of Technology, Sweden.
    Gatenholm, Paul
    Wallenberg Wood Science Center, Sweden ; Chalmers University of Technology, Sweden.
    Edelvik, Fredrik
    Fraunhofer-Chalmers Centre, Sweden.
    Simulations of 3D bioprinting: Predicting bioprintability of nanofibrillar inks2018Ingår i: Biofabrication, ISSN 1758-5082, E-ISSN 1758-5090, Vol. 10, nr 3, artikel-id 034105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    3D bioprinting with cell containing bioinks show great promise in the biofabrication of patient specific tissue constructs. To fulfil the multiple requirements of a bioink, a wide range of materials and bioink composition are being developed and evaluated with regard to cell viability, mechanical performance and printability. It is essential that the printability and printing fidelity is not neglected since failure in printing the targeted architecture may be catastrophic for the survival of the cells and consequently the function of the printed tissue. However, experimental evaluation of bioinks printability is time-consuming and must be kept at a minimum, especially when 3D bioprinting with cells that are valuable and costly. This paper demonstrates how experimental evaluation could be complemented with computer based simulations to evaluate newly developed bioinks. Here, a computational fluid dynamics simulation tool was used to study the influence of different printing parameters and evaluate the predictability of the printing process. Based on data from oscillation frequency measurements of the evaluated bioinks, a full stress rheology model was used, where the viscoelastic behaviour of the material was captured. Simulation of the 3D bioprinting process is a powerful tool and will help in reducing the time and cost in the development and evaluation of bioinks. Moreover, it gives the opportunity to isolate parameters such as printing speed, nozzle height, flow rate and printing path to study their influence on the printing fidelity and the viscoelastic stresses within the bioink. The ability to study these features more extensively by simulating the printing process will result in a better understanding of what influences the viability of cells in 3D bioprinted tissue constructs.

  • 36.
    Haeggman, Marika
    et al.
    Albaeco, Sweden.
    Moberg, Fredrik
    Albaeco, Sweden.
    Sandin, Gustav
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Planetary Boundaries analysis for Houdini Sportswear – a Pilot Study: Assessment of company performance from a planetary boundaries perspective2018Ingår i: Planetary Boundaries Assessment 2018 – This is Houdini, Houdini Sportswear , 2018, s. 37-66Kapitel i bok, del av antologi (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    This is to our knowledge the first ever corporate Planetary Boundaries analysis. It is an explorative collaboration between Houdini Sportswear, Albaeco and Mistra Future Fashion with the long-term ambition to create an open-source approach that will provide Houdini and other similar companies with a more holistic view on their sustainability efforts. Albaeco is closely tied to the Stockholm Resilience Centre (SRC), an international research centre for sustainability science at Stockholm University, known among other things for its work on planetary boundaries, resilience and ecosystem services.

    This report aims to operationalize the Planetary Boundaries framework in a business context. The framework was established in 2009 when a group of scientists (Rockström and others, 2009) identified nine global environmental boundaries we should remain within so that our societies can continue to develop in a positive way. As such the Planetary Boundaries provide a holistic way of analysing sustainability that has acquired international recognition and contributed to the UN’s Sustainable Development Goals (SDGs). Rather than a narrow focus on for example water, chemicals or energy use, a planetary boundaries approach implies covering a larger set of critical environmental factors.

    The manufacturing and consumption of clothes, like every other industry, plays a role in relation to all of the nine boundaries. For example, cotton is one of the most pesticide and water demanding crops grown; chemicals used when treating fabrics risk polluting water downstream from factories; and shell layer garments are often produced using compounds that stay in the environmental indefinitely and accumulate in the fatty tissues of wildlife and humans

    Albaeco, Houdini and Mistra Future Fashion believe that analysing the textile industry from a Planetary Boundaries perspective is an important part of a larger ambition to integrate scientific analysis and resilience thinking into projects focused on accelerating business solution for sustainability.

  • 37.
    Hellström, Anna-Karin
    et al.
    Chalmers University of Technology, Sweden.
    de la Motte, Hanna
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Syrén, Marie
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Nordstierna, Lars
    Chalmers University of Technology, Sweden.
    Bordes, Romain
    Chalmers University of Technology, Sweden.
    Enabling Textile Recycling: On/Off Dyeing2016Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Develop a novel family of environmental friendly dispersant for textile coloring embedded an on/off function for closed loop recycling.

  • 38.
    Hosseinaei, Omid
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Electrospun lignin-based carbon fibers for energy storage application2018Ingår i: The 8th Nordic Wood Biorefinery Conference: NWBC 2018 : proceedings / [ed] Hytönen Eemeli, Vepsäläinen Jessica, Espoo: VTT , 2018, s. 244-244Konferensbidrag (Övrigt vetenskapligt)
  • 39.
    Hosseinaei, Omid
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Åkerström, Mårten
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Uhlin, Anders
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Tomani, Per
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Danielsson, Sverker
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Melt spun lignin-based carbon fiber from softwood kraft lignin: effect of lignin pretreatment and fiber conversion conditions2018Ingår i: The 8th Nordic Wood Biorefinery Conference: NWBC 2018 : proceedings / [ed] Hytönen Eemeli, Vepsäläinen Jessica, Espoo: VTT , 2018, s. 157-163Konferensbidrag (Övrigt vetenskapligt)
  • 40.
    Jafri, Awer
    et al.
    Luleå University of Technology, Sweden.
    Wetterlund, Elisabeth
    Luleå University of Technology, Sweden.
    Anheden, Marie
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Kulander, Ida
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Håkansson, Åsa
    Preem AB, Sweden.
    Furusjö, Erik
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Multi-aspect evaluation of integrated forest-based biofuel productionpathways:: Part 2. economics, GHG emissions, technology maturity andproduction potentials2019Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 172, s. 1312-1328Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Promoting the deployment of forest-based drop-in and high blend biofuels is considered strategically important in Sweden but many aspects of the overall performance of the foremost production technologies are as yet unexamined. This paper evaluates the technology maturity, profitability, investment requirements, GHG performance and Swedish biofuel production potential of six commercially interesting forest-based biofuel production pathways.

    Significant heterogeneity in technology maturity was observed. Lack of technical demonstration in industrially representative scales renders the liquefaction-hydrotreatment route for drop-in biofuels less mature than its gasification-catalytic upgrading counterpart. It is a paradox that short-term priority being accorded to pathways with the lowest technology maturity. Nth-of-a-kind investments in (a) gasification-based methanol, (b) hydropyrolysis-based petrol/diesel, and (c) lignin depolymerization-based petrol/diesel were profitable for a range of plant sizes. The profitability of pulp mill-integrated small gasification units (<100 MW) goes against the common perception of gasification being economically feasible only in large scales. New low-cost options for debottlenecking production at recovery boiler-limited kraft mills appear worth investigating. GHG emission reductions ranged from 66 to 95%; a penalty was incurred for high consumption of natural gas-based hydrogen. Swedish biofuel production potentials ranged from 4 to 27 TWh/y but a more feasible upper limit is 12–15 TWh/y.

  • 41.
    Jafri, Yawer
    et al.
    Luleå University of Technology, Sweden.
    Wetterlund, Elisabeth
    Luleå University of Technology, Sweden.
    Anheden, Marie
    Kulander, Ida
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Håkansson, Åsa
    Preem AB, Sweden.
    Furusjö, Erik
    Luleå University of Technology, Sweden ; IVL Swedish Environmental Research Institute, Sweden.
    Multi-aspect evaluation of integrated forest-based biofuel production pathways: Part 1. Product yields & energetic performance2019Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 166, s. 401-413Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Forest-based biofuels are strategically important in forest-rich countries like Sweden but the technical performance of several promising production pathways is poorly documented. This study examines product yields and energy efficiencies in six commercially relevant forest-based “drop-in” and “high blend” biofuel production pathways by developing detailed spreadsheet energy balance models. The models are in turn based on pilot-scale performance data from the literature, supplemented with input from technology developers and experts. In most pathways, biofuel production is integrated with a market pulp mill and/or a crude oil refinery. Initial conversion is by pyrolysis, gasification or lignin depolymerization and intermediate products are upgraded by hydrotreatment or catalytic synthesis. While lignin oil (LO) hydrodeoxygenation had the highest expanded system efficiency, considerable uncertainty surrounds product yields owing to absence of suitable experimental data on LO upgrading. Co-feeding vacuum gas oil and fast pyrolysis oil in a fluidized catalytic cracker has a complex and uncertain effect on fossil yields, which requires further investigation. Co-locating bio-oil hydrotreatment at the refinery improves heat utilization, leading to higher system efficiencies. Explicit consideration of mill type and energy requirements is required to avoid performance misestimation as an assumption of energy surplus can confer a definite advantage.

  • 42.
    Jour, Pia
    et al.
    AkzoNobel Pulp and Performance Chemicals, Sweden.
    Lindgren, Karin
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Gutke, Katarina
    Akzo Nobel Pulp and Performance Chemicals, Sweden.
    ECF bleaching of eucalyptus kraft pulp: simulation of a mill with a high degree of closure2017Ingår i: International pulp bleaching conference / [ed] Colodette J L, Gomes F J B, Suprema Grafica e Editora , 2017, s. 106-110Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The composition of non-process elements (NPEs) in wood significantly affects the level of metals in the pulp in the bleach plant and contributes to the risk of forming precipitates. The possible degree of closure is often limited by calcium oxalate formation, mainly around the D0-stage, which can be prevented by increasing the temperature and/or decreasing the pH in this stage. This paper presents the effect of a decreased pH in the D0-stage when bleaching a eucalyptus kraft pulp as well as the influence it has on environmental parameters such as chemical oxygen demand (COD) and adsorbable organic halogens (AOX). The increased AOX measured when applying a low pH in the D0-stage was shown to be easily decomposed under process conditions. To be able to predict the effect on both the recovery cycle and the bleach plant itself as a consequence of increased closure of the bleach plant, a full mill simulation model (WinGEMS) was used based on a theoretical mill using the best available technology (BAT) in combination with data produced in laboratory trials. The model pulp mill was exclusively equipped with wash presses. According to the simulations, the effluent volume could be significantly decreased from 20.7 t/air dry tonne (ADt) pulp to 8.7 t/ADt in a D(EOP)DP sequence. Using a wood raw material with a calcium content of 520 mg/kg dry solids, no formation of calcium oxalate was predicted. However, for a wood raw material with a higher content, 800 mg/kg, calcium oxalate formation was likely to occur. By decreasing the final pH in the D0-stage from 3.0 to 2.5, formation of calcium oxalate could be avoided. At the effluent volume of 8.7 t/ADt, no fresh water was used in the bleach plant except for the water used for dilution of chemicals.

  • 43.
    Jour, Pia
    et al.
    AkzoNobel, Sweden.
    Lindgren, Karin
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Gutke, Katarina
    AkzoNobel, Sweden.
    Wallinder, Johan
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Decreased water usage in a softwood ECF bleaching sequence— full mill simulations2018Ingår i: TAPPI Journal, ISSN 0734-1415, Vol. 17, nr 6, s. 353-360Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, an elemental chlorine free (ECF) bleach plant with a D0(EOP)D1(EP)D2 sequence was studied with the aim of identifying options for significantly decreasing (fresh) water usage in the bleach plant and decreasing the effluent volume. A base-case simulation model for a softwood kraft market pulp mill was made based on a reference model representing the best available techniques as well as data produced in an extensive laboratory pulp bleaching study. This model was used to evaluate increased closure within the bleach plant and the recirculation of bleach plant effluent to the brownstock system and their effects on both the bleach plant and the recovery cycle. The results indicate that it is possible to reduce the fresh water consumption from 15 metric tons/a.d. metric ton in the base case to about 2 metric tons/a.d. metric ton, without increasing the carryover of chemical oxygen demand (COD) to the pulp machine. Nonprocess elements in wood contribute to the levels of metals found in the bleach plant and thus to the risk of precipitates such as calcium oxalate, barium sulfate, and calcium carbonate. The risk of precipitates forming is a key factor determining the possible degree of closure. In addition, chloride concentration in the black liquor is another important factor that is affected by recirculating bleach plant filtrate to the brownstock washer and by the grade of the sodium hydroxide used in the mill.

  • 44.
    Jour, Pia
    et al.
    Akzo Nobel Pulp and Performance Chemicals, Sweden.
    Lindgren, Karin
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Gutke, Katarina
    Akzo Nobel Pulp and Performance Chemicals, Sweden.
    Walllinder, Johan
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Decreased water usage in a softwood ECF bleaching sequence: full mill simulations2018Ingår i: TAPPI Journal, ISSN 0734-1415, Vol. 17, nr 6, s. 353-360Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, an elemental chlorine free (ECF) bleach plant with a D0(EOP)D1(EP)D2 sequence was studied with the aim of identifying options for significantly decreasing (fresh) water usage in the bleach plant and decreasing the effluent volume. A base-case simulation model for a softwood kraft market pulp mill was made based on a reference model representing the best available techniques as well as data produced in an extensive  laboratory pulp bleaching study. This model was used to evaluate increased closure within the bleach plant and the recirculation of bleach plant effluent to the brownstock system and their effects on both the bleach plant and the recovery cycle. The results indicate that it is possible to reduce the fresh water consumption from 15 metric tons/a.d. metric ton in the base case to about 2 metric tons/a.d. metric ton, without increasing the carryover of chemical  oxygen demand (COD) to the pulp machine. Nonprocess elements in wood contribute to the levels of metals found in the bleach plant and thus to the risk of  precipitates such as calcium oxalate, barium sulfate, and calcium carbonate. The risk of precipitates forming is a key factor determining the possible degree of closure. In addition, chloride concentration in the black liquor is another important factor that is affected by recirculating bleach plant filtrate to the brownstock washer and by the grade of the sodium hydroxide used in the mill.

  • 45.
    Kaldeus, Tahani
    et al.
    Wallenberg Wood Science Center, Sweden.
    Larsson, Per Tomas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Boujemaoui, Assya
    KTH Royal institute of technology, Sweden.
    Malmström, Eva
    KTH Royal institute of technology, Sweden.
    One-pot preparation of bi-functional cellulose nanofibrils2018Ingår i: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882XArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    Herein, we present a route to obtain bi-functional cellulose nanofibrils (CNF) by a one-pot approach using an already established functionalisation route, carboxymethylation, to which a subsequent functionalisation step, allylation or alkynation, has been added in the same reaction pot, eliminating the need of solvent exchange procedures. The total charge of the fibres and the total surface charge of the nanofibrils were determined by conductometric and polyelectrolyte titration, respectively. Furthermore, the allyl and alkyne functionalised cellulose were reacted with methyl 3-mercaptopropionate and azide-functionalised disperse red, respectively, to estimate the degree of functionalisation. The samples were further assessed by XPS and FT-IR. Physical characteristics were evaluated by CP/MAS 13C-NMR, XRD, AFM and DLS. This new approach of obtaining bi-functionalised CNF allows for a facile and rapid functionalisation of CNF where chemical handles can easily be attached and used for further modification of the fibrils. Graphical abstract: [Figure not available: see fulltext.

  • 46.
    Kam, Doron
    et al.
    Hebrew University of Jerusalem, Israel.
    Chasnitsky, Michael
    Hebrew University of Jerusalem, Israel.
    Nowogrodski, Chen
    Hebrew University of Jerusalem, Israel.
    Braslavsky, Ida
    Hebrew University of Jerusalem, Israel.
    Abitbol, Tiffany
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Magdassi, Shlomo
    Hebrew University of Jerusalem, Israel.
    Shoseyov, Oded
    Hebrew University of Jerusalem, Israel.
    Direct Cryo Writing of Aerogels via 3D Printing of Aligned Cellulose Nanocrystals Inspired by the Plant Cell Wall2019Ingår i: Colloids Interfaces, Vol. 3, nr 2, artikel-id 46Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aerogel objects inspired by plant cell wall components and structures were fabricated using extrusion-based 3D printing at cryogenic temperatures. The printing process combines 3D printing with the alignment of rod-shaped nanoparticles through the freeze-casting of aqueous inks. We have named this method direct cryo writing (DCW) as it encompasses in a single processing step traditional directional freeze casting and the spatial fidelity of 3D printing. DCW is demonstrated with inks that are composed of an aqueous mixture of cellulose nanocrystals (CNCs) and xyloglucan (XG), which are the major building blocks of plant cell walls. Rapid fixation of the inks is achieved through tailored rheological properties and controlled directional freezing. Morphological evaluation revealed the role of ice crystal growth in the alignment of CNCs and XG. The structure of the aerogels changed from organized and tubular to disordered and flakey pores with an increase in XG content. The internal structure of the printed objects mimics the structure of various wood species and can therefore be used to create wood-like structures via additive manufacturing technologies using only renewable wood-based materials.

  • 47.
    Karasu, Feyza
    et al.
    École Polytechnique Fédérale de Lausanne (EPFL), Switzerland.
    Müller, Luca
    École Polytechnique Fédérale de Lausanne (EPFL), Switzerland.
    Ridaoui, Hassan
    Rolic Technologies Ltd, Switzerland.
    Ibn ElHaj, Mohammed
    Rolic Technologies Ltd, Switzerland.
    Flodberg, Göran
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Aulin, Christian
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Axrup, Lars
    Stora Enso Karlstad, Sweden.
    Leterrier, Yves
    École Polytechnique Fédérale de Lausanne (EPFL), Switzerland.
    Organic-inorganic hybrid planarization and water vapor barrier coatings on cellulose nanofibrils substrates2018Ingår i: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 6, artikel-id 571Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cellulose nanofibrils (CNF) can be produced in the form of thin, transparent andflexible films. However, the permeability of such materials to oxygen and water vaporis very sensitive to moisture, which limits their potential for a variety of packaging andencapsulation applications. Diffusion barrier coatings were thus developed to reducethe access of water molecules to enzymatically pre-treated and carboxymethylated CNFsubstrates. The coatings were based on UV curable organic-inorganic hybrids withepoxy, tetraethylorthosilicate (TEOS) and 3-glycidoxypropyltrimethylenesilane (GPTS)precursors and additional vapor formed SiNx layers. A total of 14 monolayer andmultilayer coatings with various thickness and hybrid composition were produced andanalyzed. The water vapor transmission rate (WVTR) of the bilayer epoxy/CNF film wastwo times lower compared to that of uncoated CNF film. This was partly due to the watervapor permeability of the epoxy, a factor of two times lower than CNF. The epoxy coatingimproved the transparency of CNF, however it did not properly wet to the CNF surfacesand the interfacial adhesion was low. In contrast hybrid epoxy-silica coatings led to highadhesion levels owing to the formation of covalent interactions through condensationreactions with the OH-terminated CNF surface. The barrier and optical performance ofhybrid coated CNF substrates was similar to that of CNF coated with pure epoxy. Inaddition, the hybrid coatings provided an excellent planarization effect, with roughnessclose to 1 nm, one to two orders of magnitude lower than that of the CNF substrates.The WVTR and oxygen transmission rate values of the hybrid coated CNF laminateswere in the range 5–10 g/m2/day (at 38◦C and 50% RH) and 3–6 cm3/m2/day/bar (at23◦C and 70% RH), respectively, which matches food and pharmaceutical packagingrequirements. The permeability to water vapor of the hybrid coatings wasmoreover foundto decrease with increasing the TEOS/GPTS ratio up to 30 wt% and then increase athigher ratio, and to be much lower for thinner coatings due to further UV-induced silanolcondensation and faster evaporation of byproducts. The addition of a single 150 nmthickSiNx layer on the hybrid coated CNF improved its water vapor barrier performance bymore than 680 times, with WVTR below the 0.02 g/m2/day detection limit.

  • 48.
    Karlsson, Rose-Marie Pernilla
    et al.
    KTH Royal Institute of Technology, Sweden.
    Larsson, Per Tomas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. KTH Royal Institute of Technology, Sweden.
    Hansson, Per
    Uppsala University, Sweden.
    Wågberg, Lars
    KTH Royal Institute of Technology, Sweden.
    Thermodynamics of the Water-Retaining Properties of Cellulose-Based Networks2019Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, nr 4, s. 1603-1612Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Noncrystalline cellulose-based gel beads were used as a model material to investigate the effect of osmotic stress on a cellulosic network. The gel beads were exposed to osmotic stress by immersion in solutions with different concentrations of high molecular mass dextran and the equilibrium dimensional change of the gel beads was studied using optical microscopy. The volume fraction of cellulose was calculated from the volume of the gel beads in dextran solutions and their dry content and the relation between the cellulose volume fraction and the total osmotic pressure was thus obtained. The results show that the contribution to the osmotic pressure from counterions increases the water-retaining capacity of the beads at high osmotic pressures but also that the main factor controlling the gel bead collapse at high osmotic strains is the resistance to the deformation of the polymer chain network within the beads. Furthermore, the osmotic pressure associated with the deformation of the polymer network, which counteracts the deswelling of the beads, could be fitted to the Wall model indicating that the response of the cellulose polymer networks was independent of the charge of the cellulose. The best fit to the Wall model was obtained when the Flory-Huggins interaction parameter (χ) of the cellulose-water system was set to 0.55-0.60, in agreement with the well-established insolubility of high molecular mass β-(1,4)-d-glucan polymers in water.

  • 49.
    Karlsson, Rose-Marie Pernilla
    et al.
    KTH Royal Institute of Technology, Sweden.
    Larsson, Per Tomas
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi. KTH Royal Institute of Technology, Sweden.
    Yu, Shun
    KTH Royal Institute of Technology, Sweden.
    Pendergraph, Samuel
    RISE - Research Institutes of Sweden, Bioekonomi, Papperstillverkning och förpackningar.
    Pettersson, Torbjörn
    KTH Royal Institute of Technology, Sweden.
    Hellwig, Johannes
    KTH Royal Institute of Technology, Sweden.
    Wågberg, Lars
    KTH Royal Institute of Technology, Sweden.
    Carbohydrate gel beads as model probes for quantifying non-ionic and ionic contributions behind the swelling of delignified plant fibers.2018Ingår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 519, s. 119-129, artikel-id S0021-9797(18)30200-5Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Macroscopic beads of water-based gels consisting of uncharged and partially charged β-(1,4)-d-glucan polymers were developed to be used as a novel model material for studying the water induced swelling of the delignified plant fiber walls. The gel beads were prepared by drop-wise precipitation of solutions of dissolving grade fibers carboxymethylated to different degrees. The internal structure was analyzed using Solid State Cross-Polarization Magic Angle Spinning Carbon-13 Nuclear Magnetic Resonance and Small Angle X-ray Scattering showing that the internal structure could be considered a homogeneous, non-crystalline and molecularly dispersed polymer network. When beads with different charge densities were equilibrated with aqueous solutions of different ionic strengths and/or pH, the change in water uptake followed the trends expected for weak polyelectrolyte gels and the trends found for cellulose-rich fibers. When dried and subsequently immersed in water the beads also showed an irreversible loss of swelling depending on the charge and type of counter-ion which is commonly also found for cellulose-rich fibers. Taken all these results together it is clear that the model cellulose-based beads constitute an excellent tool for studying the fundamentals of swelling of cellulose rich plant fibers, aiding in the elucidation of the different molecular and supramolecular contributions to the swelling.

  • 50.
    Koppolu, R.
    et al.
    Åbo Akademi University, Finland.
    Lahti, J.
    Tampere University of Technology, Finland.
    Abitbol, Tiffany
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Swerin, Agne
    Kuusipalo, J.
    Tampere University of Technology, Finland.
    Toivakka, M.
    Åbo Akademi University, Finland.
    Continuous Processing of Nanocellulose and Polylactic Acid into Multilayer Barrier Coatings2019Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, nr 12, s. 11920-11927Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent years have seen an increased interest toward utilizing biobased and biodegradable materials for barrier packaging applications. Most of the abovementioned materials usually have certain shortcomings that discourage their adoption as a preferred material of choice. Nanocellulose falls into such a category. It has excellent barrier against grease, mineral oils, and oxygen but poor tolerance against water vapor, which makes it unsuitable to be used at high humidity. In addition, nanocellulose suspensions' high viscosity and yield stress already at low solid content and poor adhesion to substrates create additional challenges for high-speed processing. Polylactic acid (PLA) is another potential candidate that has reasonably high tolerance against water vapor but rather a poor barrier against oxygen. The current work explores the possibility of combining both these materials into thin multilayer coatings onto a paperboard. A custom-built slot-die was used to coat either microfibrillated cellulose or cellulose nanocrystals onto a pigment-coated baseboard in a continuous process. These were subsequently coated with PLA using a pilot-scale extrusion coater. Low-density polyethylene was used as for reference extrusion coating. Cationic starch precoating and corona treatment improved the adhesion at nanocellulose/baseboard and nanocellulose/PLA interfaces, respectively. The water vapor transmission rate for nanocellulose + PLA coatings remained lower than that of the control PLA coating, even at a high relative humidity of 90% (38 °C). The multilayer coating had 98% lower oxygen transmission rate compared to just the PLA-coated baseboard, and the heptane vapor transmission rate reduced by 99% in comparison to the baseboard. The grease barrier for nanocellulose + PLA coatings increased 5-fold compared to nanocellulose alone and 2-fold compared to PLA alone. This approach of processing nanocellulose and PLA into multiple layers utilizing slot-die and extrusion coating in tandem has the potential to produce a barrier packaging paper that is both 100% biobased and biodegradable.

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