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Yang, J., Zasadowski, D., Edlund, H. & Norgren, M. (2019). Biorefining of Spruce TMP Process Water: Selective Fractionation of Lipophilic Extractives with Induced Air Flotation and Surface Active Additive. BioResources, 14(2), 4124-4135
Öppna denna publikation i ny flik eller fönster >>Biorefining of Spruce TMP Process Water: Selective Fractionation of Lipophilic Extractives with Induced Air Flotation and Surface Active Additive
2019 (Engelska)Ingår i: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 14, nr 2, s. 4124-4135Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Lignocellulose biomass plays an important role in reducing thedependency on fossil fuels and ameliorating the dire consequences ofclimate change. It is therefore important that all the components oflignocellulose biomass are exploited. These components includehemicelluloses and extractives that are liberated and sterically stabilizedduring the thermomechanical pulping and that form the dissolved andcolloidal substance (DCS) in the process water. Biorefining of this processwater can extract these substances, which have a number of promisingapplications and can contribute to the full exploitation of lignocellulosebiomass. This paper presents a simple treatment of unbleached Norwayspruce (Picea abies) process water from TMP (thermomechanical pulping)production using induced air flotation (IAF) and cationic surfactant,dodecyl trimethylammonium chloride (DoTAC) to refine the extractivesand prepare the waters so that hemicellulose could be easily harvested ata later stage. By applying 80 ppm of DoTAC at a pH of 3.5 and 50 °Cbefore induced air flotation, 94% of the lipophilic extractives wererecovered from process water. Dissolved hemicellulose polysaccharideswere cleansed and left in the treated process water. The process enabledefficient biorefining of lipophilic extractives and purification of the processwater to enable more selective harvesting of hemicelluloses in subsequentsteps.

Nyckelord
Biorefining; Lipophilic extractives; Thermomechanical pulping; Induced air flotation
Nationell ämneskategori
Kemiteknik
Identifikatorer
urn:nbn:se:miun:diva-35955 (URN)10.15376/biores.14.2.4124-4135 (DOI)000466449000115 ()2-s2.0-85071077339 (Scopus ID)
Projekt
EU Reginal fund 2
Forskningsfinansiär
Europeiska regionala utvecklingsfonden (ERUF)
Tillgänglig från: 2019-04-05 Skapad: 2019-04-05 Senast uppdaterad: 2019-09-03Bibliografiskt granskad
Costa, C., Medronho, B., Filipe, A., Mira, I., Lindman, B., Edlund, H. & Norgren, M. (2019). Emulsion formation and stabilization by biomolecules: The leading role of cellulose. Polymers, 11(10), Article ID 1570.
Öppna denna publikation i ny flik eller fönster >>Emulsion formation and stabilization by biomolecules: The leading role of cellulose
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2019 (Engelska)Ingår i: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 11, nr 10, artikel-id 1570Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Emulsion stabilization by native cellulose has been mainly hampered because of its insolubility in water. Chemical modification is normally needed to obtain water-soluble cellulose derivatives. These modified celluloses have been widely used for a range of applications by the food, cosmetic, pharmaceutic, paint and construction industries. In most cases, the modified celluloses are used as rheology modifiers (thickeners) or as emulsifying agents. In the last decade, the structural features of cellulose have been revisited, with particular focus on its structural anisotropy (amphiphilicity) and the molecular interactions leading to its resistance to dissolution. The amphiphilic behavior of native cellulose is evidenced by its capacity to adsorb at the interface between oil and aqueous solvent solutions, thus being capable of stabilizing emulsions. In this overview, the fundamentals of emulsion formation and stabilization by biomolecules are briefly revisited before different aspects around the emerging role of cellulose as emulsion stabilizer are addressed in detail. Particular focus is given to systems stabilized by native cellulose, either molecularly-dissolved or not (Pickering-like effect). 

Nyckelord
Adsorption, Amphiphilicity, Cellulose, Emulsion stability, Oil-water interface
Nationell ämneskategori
Kemiteknik
Identifikatorer
urn:nbn:se:miun:diva-37680 (URN)10.3390/polym11101570 (DOI)2-s2.0-85073478887 (Scopus ID)
Tillgänglig från: 2019-11-14 Skapad: 2019-11-14 Senast uppdaterad: 2019-11-14Bibliografiskt granskad
Costa, C., Mira, I., Benjamins, J.-W., Lindman, B., Edlund, H. & Norgren, M. (2019). Interfacial activity and emulsion stabilization of dissolved cellulose. Journal of Molecular Liquids, 292, Article ID 111325.
Öppna denna publikation i ny flik eller fönster >>Interfacial activity and emulsion stabilization of dissolved cellulose
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2019 (Engelska)Ingår i: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 292, artikel-id 111325Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Some aspects of the interfacial behavior of cellulose dissolved in an aqueous solvent were investigated. Cellulose was found to significantly decrease the interfacial tension (IFT) between paraffin oil and 85 wt% phosphoric acid aqueous solutions. This decrease was similar in magnitude to that displayed by non-ionic cellulose derivatives. Cellulose's interfacial activity indicated a significant amphiphilic character and that the interfacial activity of cellulose derivatives is not only related to the derivatization but inherent in the cellulose backbone. This finding suggests that cellulose would have the ability of stabilizing dispersions, like oil-in-water emulsions in a similar way as a large number of cellulose derivatives. In its molecularly dissolved state, cellulose proved to be able to stabilize emulsions of paraffin in the polar solvent on a short-term. However, long-term stability against drop-coalescence was possible to achieve by a slight change in the amphiphilicity of cellulose, effected by a slight increase in pH. These emulsions exhibited excellent stability against coalescence/oiling-off over a period of one year. Ageing of the cellulose solution before emulsification (resulting in molecular weight reduction) was found to favour the creation of smaller droplets. 

Nyckelord
Adsorption, Amphiphilicity, Cellulose molecules, Emulsions, Interfacial activity, Oil-water interface
Nationell ämneskategori
Kemiteknik
Identifikatorer
urn:nbn:se:miun:diva-36838 (URN)10.1016/j.molliq.2019.111325 (DOI)000488658900015 ()2-s2.0-85069688256 (Scopus ID)
Anmärkning

Available under a Creative Commons license https://creativecommons.org/licenses/by/4.0/

Tillgänglig från: 2019-08-13 Skapad: 2019-08-13 Senast uppdaterad: 2019-11-13Bibliografiskt granskad
Eivazihollagh, A., Svanedal, I., Edlund, H. & Norgren, M. (2019). On chelating surfactants: Molecular perspectives and application prospects. Journal of Molecular Liquids, 278, 688-705
Öppna denna publikation i ny flik eller fönster >>On chelating surfactants: Molecular perspectives and application prospects
2019 (Engelska)Ingår i: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 278, s. 688-705Artikel i tidskrift, Editorial material (Refereegranskat) Published
Abstract [en]

Chelating agents, molecules that very strongly coordinates certain metal ions, are used industrially as well as in consumer products to minimize disturbances and increase performance of reactions and applications. The widely used sequestering agents, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) belong to this branch of readily water-soluble compounds. When these chemical structures also have hydrophobic parts, they are prone to adsorb at air-water interfaces and to self-assemble. Such bifunctional molecules can be called chelating surfactants and will have more extended utilization prospects than common chelating agents or ordinary ionic surfactants. The present review attempts to highlight the fundamental behavior of chelating surfactants in solution and at interfaces, and their very specific interactions with metal ions. Methods to recover chelating surfactants from metal chelates are also described. Moreover, utilization of chelating surfactants in applications for metal removal in environmental engineering and mineral processing, as well as for metal control in the fields of biology, chemistry and physics, is exemplified and discussed.

Nyckelord
Chelating surfactants, Metallosurfactants, Amphiphiles, Self-assembly, Metal-coordination, Sequestering agents, Complexing agents, Remediation, Flotation, Metal recovery, Recovery, Catalysis, Metalloenzymes, Contrast agents, Nanoparticle synthesis, Applications
Nationell ämneskategori
Mineral- och gruvteknik Nanoteknik Biosanering Vattenbehandling Miljöledning Pappers-, massa- och fiberteknik Biomaterial Biokatalys och enzymteknik Kemiteknik Annan kemiteknik Övrig annan teknik
Identifikatorer
urn:nbn:se:miun:diva-35610 (URN)10.1016/j.molliq.2019.01.076 (DOI)000461526600074 ()2-s2.0-85061119211 (Scopus ID)
Tillgänglig från: 2019-02-08 Skapad: 2019-02-08 Senast uppdaterad: 2019-05-20Bibliografiskt granskad
Yang, J., Dahlström, C., Edlund, H., Lindman, B. & Norgren, M. (2019). pH-responsive cellulose–chitosan nanocomposite films with slow release of chitosan. Cellulose (London), 26(6), 3763-3776
Öppna denna publikation i ny flik eller fönster >>pH-responsive cellulose–chitosan nanocomposite films with slow release of chitosan
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2019 (Engelska)Ingår i: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 26, nr 6, s. 3763-3776Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Cellulose–chitosan films were preparedusing a physical method in which cellulose andchitosan were separately dissolved via freeze thawingin LiOH/urea and mixed in different proportions, theresulting films being cast and regenerated in water/ethanol. X-ray diffraction and Fourier transforminfrared spectroscopy (FT-IR) spectroscopy verifiedthe composition changes in the nanocomposites due todifferent mixing ratios between the polymers. Tensilestress–strain measurements indicated that the mechan-ical performance of the cellulose–chitosan nanocom-posites slightly worsened with increasing chitosancontent compared with that of films comprisingcellulose alone. Field emission scanning electronmicroscopy revealed the spontaneous formation ofnanofibers in the films; these nanofibers were subse-quently ordered into lamellar structures. Water uptakeand microscopy analysis of film thickness changesindicated that the swelling dramatically increased atlower pH and with increasing chitosan content, thisbeing ascribed to the Gibbs–Donnan effect. Slowmaterial loss appeared at acidic pH, as indicated by aloss of weight, and quantitative FT-IR analysisconfirmed that chitosan was the main componentreleased.Asample containing 75% chitosan reached amaximum swelling ratio and weight loss of 1500%and 55 wt%, respectively, after 12 h at pH 3. Thestudy presents a novel way of preparing pH-responsivecellulose–chitosan nanocomposites with slow-releasecharacteristics using an environmentally friendlyprocedure and without any chemical reactions.

Nyckelord
Cellulose dissolution, Chitosan dissolution, pH responsive, Gibbs–Donnan equilibrium, Nanocomposite, Slow release
Nationell ämneskategori
Annan kemiteknik
Identifikatorer
urn:nbn:se:miun:diva-35778 (URN)10.1007/s10570-019-02357-5 (DOI)000464849500011 ()2-s2.0-85062686323 (Scopus ID)
Forskningsfinansiär
Forskningsrådet Formas, 942-2015-251
Tillgänglig från: 2019-03-12 Skapad: 2019-03-12 Senast uppdaterad: 2019-09-03Bibliografiskt granskad
Eivazihollagh, A., Löf, L., Lindman, B., Norgren, M. & Edlund, H. (2019). Vesicle-templated all-cellulose nanocapsules. In: : . Paper presented at 6th EPNOE International Polysaccharide Conference, Aveiro, Portugal, 21–25 October, 2019.
Öppna denna publikation i ny flik eller fönster >>Vesicle-templated all-cellulose nanocapsules
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2019 (Engelska)Konferensbidrag, Poster (med eller utan abstract) (Refereegranskat)
Abstract [en]

Polymeric multilayers capsules constructed using the layer-by-layer (LbL) technique are interesting candidates for the purposes of storage, encapsulation and release in a wide range of biomedical applications. In the current study, cellulose-based nanocapsules were produced via the LbL technique. In this procedure, alternating deposition of the two biocompatible polymers anionic cellulose, carboxymethylcellulose (CMC), and cationic cellulose, quaternized hydroxyethylcellulose ethoxylate (QHECE), on a cationic vesicular template made of didodecyldimethylammonium bromide (DDAB), was performed. The obtained nanocapsules, were characterized by dynamic light scattering (DLS), ⇣ potential measurements, and field-emission scanning electron microscopy (FE-SEM). DLS measurements revealed that the size of the spheres is about hundreds of nanometer with polydispersity index (PDI) values between 0.2 and 0.3, indicating a relatively homogeneous size distribution. In addition, FESEM characterization also indicated the shape and size of obtained material. The surface charge analysis of the nanocapsules by ⇣ potential measurements indicated the presence of electrostatically stabilized nanoparticles. The values of diameter, PDI and surface charge for cationic vesicles coated by CMC were 204 nm, 0.26 and –38 mV, respectively. After deposition of QHECE, the diameter, PDI, and surface charge were about 265 nm, 0.36 and +32.5 mV, respectively. Figure 1 shows FE-SEM images of cellulose nanoparticles fabricated via LbL deposition of polyelectrolyte layers. As seen in the microscopy images, the shape of the core-shell particles are not fully spherical which could be due to drying e↵ects of the sample before FE-SEM characterization. The construction of cellulose nanocontainers by using an alternating deposition of oppositely charged biobased polyelectrolytes on vesicles o↵ers several advantages such as simplicity, reproducibility, biocompatibility, low-cost, mild reaction conditions, and high controllability over the thickness and composition of the shell.

Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
urn:nbn:se:miun:diva-37815 (URN)
Konferens
6th EPNOE International Polysaccharide Conference, Aveiro, Portugal, 21–25 October, 2019
Forskningsfinansiär
ÅForsk (Ångpanneföreningens Forskningsstiftelse)
Tillgänglig från: 2019-11-28 Skapad: 2019-11-28 Senast uppdaterad: 2019-12-09Bibliografiskt granskad
Eivazihollagh, A., Norgren, M., Dahlström, C. & Edlund, H. (2018). Controlled Synthesis of Cu and Cu2O NPs and Incorporation of Octahedral Cu2O NPs in Cellulose II Films. Nanomaterials, 8(4), Article ID 238.
Öppna denna publikation i ny flik eller fönster >>Controlled Synthesis of Cu and Cu2O NPs and Incorporation of Octahedral Cu2O NPs in Cellulose II Films
2018 (Engelska)Ingår i: Nanomaterials, ISSN 2079-4991, Vol. 8, nr 4, artikel-id 238Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

In this study, Cu and Cu2O nanoparticles (NPs) were synthesized through chemical reduction of soluble copper-chelating ligand complexes using formaldehyde as a reducing agent. The influence of various chelating ligands, such as ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), and a surface-active derivative of DTPA (C12-DTPA), as well as surfactants (i.e., hexadecyltrimethylammonium bromide (CTAB), dodecyltrimethylammonium chloride (DoTAC), sodium dodecyl sulfate (SDS), and dimethyldodecylamine-N-oxide (DDAO)), on morphology and the composition of produced NPs was investigated. In the absence of surfactants, spherical copper particles with polycrystalline structure could be obtained. X-ray diffraction (XRD) analysis revealed that, in the presence of EDTA, the synthesized NPs are mainly composed of Cu with a crystallite size on the order of 35 nm, while with DTPA and C12-DTPA, Cu2O is also present in the NPs as a minority phase. The addition of ionic surfactants to the copper–EDTA complex solution before reduction resulted in smaller spherical particles, mainly composed of Cu. However, when DDAO was added, pure Cu2O nano-octahedrons were formed, as verified by high-resolution scanning electron microscopy (HR-SEM) and XRD. Furthermore, a hybrid material could be successfully prepared by mixing the octahedral Cu2O NPs with cellulose dissolved in a LiOH/urea solvent system, followed by spin-coating on silica wafers. It is expected that this simple and scalable route to prepare hybrid materials could be applied to a variety of possible applications.

Nyckelord
copper nanoparticles; cuprous oxide nano-octahedrons; hybrid material; regenerated cellulose; chemical reduction; chelating agent; surfactant
Nationell ämneskategori
Nanoteknik Kemiteknik Materialteknik
Identifikatorer
urn:nbn:se:miun:diva-33497 (URN)10.3390/nano8040238 (DOI)000434889100059 ()2-s2.0-85045875998 (Scopus ID)
Tillgänglig från: 2018-04-16 Skapad: 2018-04-16 Senast uppdaterad: 2018-07-04Bibliografiskt granskad
Ibrahem, I., Iqbal, M. N., Verho, O., Eivazihollagh, A., Olsén, P., Edlund, H., . . . Johnston, E. V. (2018). Copper Nanoparticles on Controlled Pore Glass and TEMPO for the Aerobic Oxidation of Alcohols. ChemNanoMat, 4(1), 71-75
Öppna denna publikation i ny flik eller fönster >>Copper Nanoparticles on Controlled Pore Glass and TEMPO for the Aerobic Oxidation of Alcohols
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2018 (Engelska)Ingår i: ChemNanoMat, ISSN 2199-692X, Vol. 4, nr 1, s. 71-75Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Herein, we report on the facile synthesis of a heterogeneous copper nanocatalyst and its combination with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) for the aerobic oxidation of alcohols to their corresponding carbonyl compounds. This low cost copper nanocatalyst was found to exhibit excellent recyclability, making it a highly attractive catalytic system from an economical and environmental point of view. Extensive characterization of the catalyst by a number of techniques revealed that it was comprised of well-dispersed Cu(I/II) nanoparticles with an average size of around 6nm.

Nyckelord
Alcohol oxidation, Copper nanoparticles, Green chemistry, Heterogeneous catalysis, TEMPO
Nationell ämneskategori
Kemi
Identifikatorer
urn:nbn:se:miun:diva-32328 (URN)10.1002/cnma.201700309 (DOI)000419237800011 ()2-s2.0-85033664510 (Scopus ID)
Anmärkning

Version of record online: 14 November 2017

Tillgänglig från: 2017-12-07 Skapad: 2017-12-07 Senast uppdaterad: 2019-08-06Bibliografiskt granskad
Lundberg, M., Norgren, M. & Edlund, H. (2018). Crill Measurements For Improved Fines Material Control. In: IMPC 2018: . Paper presented at International Mechanical Pulping Conference (IMPC) 2018, May 27-30, 2018, Trondheim, Norway. Trondheim, Norway
Öppna denna publikation i ny flik eller fönster >>Crill Measurements For Improved Fines Material Control
2018 (Engelska)Ingår i: IMPC 2018, Trondheim, Norway, 2018Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Finding the characterization method that best matches the pulping process is crucial in enabling the monitoring and control of pulp and final-product properties. Control of optimal process parameters in the production line are thus dependent on reliable and valid results. The Crill method is an analogue method based on the relationship between the interactions of lights of two different wavelengths (UV and IR) with the particles in the pulp. By comparing the specific UV and IR surfaces, the crill value is calculated. The crill method has been used in two studies with the aims to validate the crill measurement in a high yield pulping (HYP) process by focusing on refining and control of crill value of different pulp streams. The results indicate that the crill method can be used to monitor fibre treatment in refining processes. Moreover, by controlling pulp streams with regards to crill value, improvements of pulp strength and retention on the paper machine (PM) can be achieved.

Ort, förlag, år, upplaga, sidor
Trondheim, Norway: , 2018
Nationell ämneskategori
Pappers-, massa- och fiberteknik
Identifikatorer
urn:nbn:se:miun:diva-34678 (URN)
Konferens
International Mechanical Pulping Conference (IMPC) 2018, May 27-30, 2018, Trondheim, Norway
Tillgänglig från: 2018-10-09 Skapad: 2018-10-09 Senast uppdaterad: 2018-10-09Bibliografiskt granskad
Eivazihollagh, A., Bäckström, J., Norgren, M. & Edlund, H. (2018). Electrochemical recovery of copper complexed by DTPA and C12-DTPA from aqueous solution using a membrane cell. Journal of chemical technology and biotechnology (1986), 93(5), 1421-1431
Öppna denna publikation i ny flik eller fönster >>Electrochemical recovery of copper complexed by DTPA and C12-DTPA from aqueous solution using a membrane cell
2018 (Engelska)Ingår i: Journal of chemical technology and biotechnology (1986), ISSN 0268-2575, E-ISSN 1097-4660, Vol. 93, nr 5, s. 1421-1431Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

BACKGROUND

The electrochemical recovery of copper from DTPA and C12-DTPA (a surface-active derivative of DTPA) complex solutions was investigated in a membrane flow cell. Electrolysis time, solution flow rate, applied current density, and solution pH were evaluated.

RESULTS

The chelating surfactant C12-DTPA can promote the kinetics of copper electrodeposition more than DTPA depending on the experimental conditions. At a current density of 30 A m–2, a solution flow rate of 0.6 L min–1, and pH 10 after 180 min treatment, the copper recovery and current efficiency were 50% and 43.3%, respectively, in the Cu(II)-DTPA system and about 65% and 53.6%, respectively, in the Cu(II)-C12-DTPA system. The differences in the amount of recovery could be explained in terms of differences in the diffusion of copper complexes with DTPA and C12-DTPA to the cathode, as well as their solution behavior and pH-dependent conditional stability constants (log10 K’CuDTPA3-).

CONCLUSION

Electrochemical methods could be effectively combined with foam flotation for the chelating surfactant C12-DTPA, to recover copper and C12-DTPA. This makes the overall treatment more sustainable, and can be helpful in complying with the increasingly stringent environmental regulations

Nationell ämneskategori
Kemi
Identifikatorer
urn:nbn:se:miun:diva-32251 (URN)10.1002/jctb.5510 (DOI)000429714500022 ()2-s2.0-85040192944 (Scopus ID)
Anmärkning

Tillgänglig från: 2017-12-05 Skapad: 2017-12-05 Senast uppdaterad: 2019-03-15Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-5579-3373

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