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  • 1.
    Bui, Thai Q.
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Swede.
    Konwar, Lakhya Jyoti
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden.
    Samikannu, Ajaikumar
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Mikkola, Jyri-Pekka
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden. Laboratory of Industrial Chemistry and Reaction Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, FI-20500 Turku, Finland.
    Mesoporous Melamine-Formaldehyde Resins as Efficient Heterogeneous Catalysts for Continuous Synthesis of Cyclic Carbonates from Epoxides and Gaseous CO22020In: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 8, no 34, p. 12852-12869Article in journal (Refereed)
    Abstract [en]

    Herein, we report the application of inexpensive mesoporous melamine-formaldehyde resins (MMFR and MMFR250) obtained by a novel template-free and organosolvent-free hydrothermal method as efficient heterogeneous catalysts for direct synthesis of cyclic carbonates from CO2 and epoxides (epichlorohydrin, butylene oxide, and styrene oxide). The catalytic activities of the melamine resins were attributed to the abundant Lewis basic N-sites capable of activating CO2 molecules. Based on CO2-temperature programmed desorption, the concentrations of surface basic sites for MMFR and MMFR250 were estimated to be 172 and 56 μmol/g, while the activation energies of CO2 desorption (strength of basic sites) were calculated to be 92.1 and 64.5 kJ/mol. We also observed considerable differences in the catalytic activities and stabilities of polymeric catalysts in batch and in continuous-flow mode due to the existence of a synergism between adsorption of CO2 and cyclic carbonates (poison). Our experiments also revealed the important role of catalyst surface chemistry and CO2 partial pressure upon catalyst poisoning. Nevertheless, owing to their unique properties (large specific surface area, large mesoporous, and CO2 basicity), melamine resins presented excellent activities (turnover frequency 207–2147 h–1) and selectivities (>99%) for carbonation of epoxides with CO2 (20 bar initial CO2 or CO2:epoxide mole ratio ∼1.5) under solvent-free and co-catalyst-free conditions at 100–120 °C. Most importantly, these low-cost polymeric catalysts were reusable and demonstrated exceptional stability in a flow reactor (tested up to 13 days of time on stream, weight hourly space velocity 0.26–1.91 h–1) for continuous cyclic carbonate production from gaseous CO2 with different epoxides (conversion 76–100% and selectivity >99%) under industrially relevant conditions (120 °C, 13 bar, solvent-free/co-catalyst-free) confirming their superiority over the previously reported catalytic materials.

  • 2.
    Elbadawi, Mohammed
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems. Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Gustafsson, Thomas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Gaisford, S.
    Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
    Basit, A.W.
    Department of Pharmaceutics, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
    Pressure-assisted microsyringe 3D printing of oral films based on pullulan and hydroxypropyl methylcellulose2021In: International Journal of Pharmaceutics, ISSN 0378-5173, E-ISSN 1873-3476, Vol. 595, article id 120197Article in journal (Refereed)
    Abstract [en]

    Oral films (OFs) continue to attract attention as drug delivery systems, particularly for pedatric and geriatric needs. However, immiscibility between different polymers limits the full potential of OFs from being explored. One example is pullulan (PUL), a novel biopolymer which often has to be blended with other polymers to reduce cost and alter its mechanical properties. In this study, the state-of-the-art in fabrication techniques, three-dimensional (3D) printing was used to produce hybrid film structures of PUL and hydroxypropyl methylcellulose (HPMC), which were loaded with caffeine as a model drug. 3D printing was used to control the spatial deposition of films. HPMC was found to increase the mean mechanical properties of PUL films, where the tensile strength, elastic modulus and elongation break increased from 8.9 to 14.5 MPa, 1.17 to 1.56 GPa and from 1.48% to 1.77%, respectively. In addition, the spatial orientation of the hybrid films was also explored to determine which orientation could maximize the mechanical properties of the hybrid films. The results revealed that 3D printing could modify the mechanical properties of PUL whilst circumventing the issues associated with immiscibility.

  • 3.
    Jablonski, Piotr
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Warna, Johan
    Industrial Chemistry & Reaction Engineering, Department of Chemical Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, FI-20500 Åbo-Turku, Finland.
    Irgum, Knut
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden.
    Mikkola, Jyri-Pekka
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden; Industrial Chemistry & Reaction Engineering, Department of Chemical Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, FI-20500 Åbo-Turku, Finland.
    Khokarale, Santosh Govind
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden.
    Sustainable, highly selective, and metal-free thermal depolymerization of poly-(3-hydroxybutyrate) to crotonic acid in recoverable ionic liquids2022In: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 24, no 10, p. 4130-4139Article in journal (Refereed)
    Abstract [en]

    Valorization of renewable and biodegradable biopolymers to value added chemicals and green fuels is currently considered as an important research topic aiming at reducing the dependency on fossil derived feedstocks as well as their negative consequences on the environment. In this report, we are introducing an ionic liquid (IL) mediated, sustainable, and green synthesis of crotonic acid (CA) from poly-(3-hydroxybutyrate, PHB), a biopolymer derived from microbial fermentation. In this actual case, imidazolium cation comprising ILs have been used in the synthesis, where the influence of various reaction parameters such as reaction temperature and types of ILs as well as the amount of polymer, water, and IL in the reaction mixture were examined. The conversion of PHB to CA in IL took place by a base catalyzed depolymerization with formation of crotonyl terminated polymeric entities as intermediates, a mechanism that was confirmed by NMR analysis of the reaction mixtures sampled when the reactions were carried out at various temperatures. The rate of CA formation via the IL mediated base catalyzed depolymerization increased with increasing temperature in the tested interval, and 97% yield of CA was obtained after 90 min at 140 degrees C. The [EMIM][AcO] IL applied as solvent and catalyst is capable of completely depolymerizing PHB to CA in 5 h at 120 degrees C up to a polymer loading of 40 wt%. At higher loadings the depolymerization became incomplete, which is attributed to a deactivation of the IL due to hydrogen bonding interactions with the in situ formed CA, confirmed by NMR and DSC techniques. Since the depolymerization is base catalyzed, the only tested ILs that were able to form CA were based on acetate anions, whereas the less basic or neutral [EMIM][Cl] IL was found to be inactive. Finally, more than 90% of CA as well as [EMIM][AcO] IL were recovered in high purity by solvent extraction with brine (saturated aqueous NaCl) and 2-methyl tetrahydrofuran (2-Me-THF). Most importantly, here we introduce a sustainable, metal free, and single solvent based reaction approach for selective depolymerization of PHB to industrially valuable CA in basic and recoverable ILs.

  • 4.
    Khasevani, Sepideh G.
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Ojwang, Dickson O.
    Department of Chemistry – Ångström Laboratory, Uppsala University, Box 538, SE-751 21, Uppsala, Sweden.
    Nodari, Luca
    Dipartimento di Scienze Chimiche, Università degli Studi di Padova, 35131 Padova, Italy; Istituto di Chimica della Materia Condensata e di Tecnologie per l’Energia, ICMATE-CNR, 35127 Padova, Italy.
    Sarmad, Shokat
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90871 Umeå, Sweden.
    Mikkola, Jyri-Pekka
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90871 Umeå, Sweden; Industrial Chemistry & Reaction Engineering, John Gadolin Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, Fl-20500 Åbo-Turku, Finland.
    Rigoni, Federica
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30170 Venezia-Mestre, Italy.
    Concina, Isabella
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    The beauty of being complex: Prussian blue analogues as selective catalysts and photocatalysts in the degradation of ciprofloxacin2022In: Journal of Catalysis, ISSN 0021-9517, E-ISSN 1090-2694, Vol. 410, p. 307-319Article in journal (Refereed)
    Abstract [en]

    We investigate the performance of four Prussian blue analogues (PBAs) as catalysts for the selective degradation of ciprofloxacin in water, under both dark and illumination conditions. We show that no light is actually needed to induce a selective degradation of the molecular target, while light irradiation spurs the process, without, however, resulting in the commonly reported photolysis-supported breaking down. We present a systematic characterization of the PBAs aiming at interpreting the catalytic outcomes in the light of a classic coordination chemistry analysis, empowered by the most recent findings in literature. We show that varying the transition metal binding the N atom of the cyanide bridge is key to promote photoinduced charge generation and transfer, which effectively disrupts the molecular target. The analysis of the materials before and after the irradiation with solar simulated light results in a change of the lattice parameters, indicating the possibility of a light-induced spin cross-over.

  • 5.
    Khasevani, Sepideh Gholizadeh
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Chaxel, Cécile
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Sarmad, Shokat
    Wallenberg Wood Science Center, Department of Chemistry Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90871 Umeå, Sweden.
    Mikkola, Jyri-Pekka
    Wallenberg Wood Science Center, Department of Chemistry Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90871 Umeå, Sweden; Industrial Chemistry & Reaction Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, FI-20500 Åbo-Turku, Finland.
    Concina, Isabella
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Empowering Adsorption and Photocatalytic Degradation of Ciprofloxacin on BiOI Composites: A Material-by-Design Investigation2023In: ACS Omega, E-ISSN 2470-1343, Vol. 8, no 46, p. 44044-44056Article in journal (Refereed)
    Abstract [en]

    Binary and ternary composites of BiOI with NH2-MIL-101(Fe) and a functionalized biochar were synthesized through an in situ approach, aimed at spurring the activity of the semiconductor as a photocatalyst for the removal of ciprofloxacin (CIP) from water. Experimental outcomes showed a drastic enhancement of the adsorption and the equilibrium (which increased from 39.31 mg g–1 of bare BiOI to 76.39 mg g–1 of the best ternary composite in 2 h time), while the kinetics of the process was not significantly changed. The photocatalytic performance was also significantly enhanced, and the complete removal of 10 ppm of CIP in 3 h reaction time was recorded under simulated solar light irradiation for the best catalyst of the investigated batch. Catalytic reactions supported by different materials obeyed different reaction orders, indicating the existence of different mechanisms. The use of scavengers for superoxide anion radicals, holes, and hydroxyl radicals showed that although all these species are involved in CIP photodegradation, the latter play the most crucial role, as also confirmed by carrying out the reaction at increasing pH conditions. A clear correlation between the reduction of BiOI crystallite sizes in the composites, as compared to the bare material, and the material performance as both adsorbers and photocatalyst was identified. 

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  • 6.
    Khokarale, Santosh Govind
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden.
    Jablonski, Piotr
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Dinh, Van Minh
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden.
    Sundman, Ola
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden.
    Irgum, Knut
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden.
    Mikkola, Jyri-Pekka
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, S-90187 Umeå, Sweden; Industrial Chemistry & Reaction Engineering, Department of Chemical Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, FI-20500 Åbo-Turku, Finland.
    Poly (Vinylidene Difluoride) Polymer in 1-Ethyl-3-methylimidazolium Acetate and Acetic Acid Containing Solvents: Tunable and Recoverable Solvent Media to Induce Crystalline Phase Transition and Porosity2022In: Sustainable Chemistry, E-ISSN 2673-4079, Vol. 3, no 4, p. 455-474Article in journal (Refereed)
    Abstract [en]

    In this report, 1-ethyl-3-methylimidazolium acetate, [EMIM][AcO] ionic liquid (IL) and acetic acid (AA) comprised solvents were used for the thermal treatment of poly (vinylidene difluoride), PVDF. Here, besides the various combinations of IL and AA in solvents, the pure IL and AA were also applied as a solvent upon thermal treatments. The samples obtained after the treatment were analysed for structural and crystalline phase changes, porosity, and molecular weight distribution with various analytical techniques. The Kamlet-Taft parameters measurement of the IL and AA containing solvents with different solvatochromic dyes was also performed to examine their solvent properties and correlate with the properties of the treated PVDF materials. The treatment of PVDF with pure IL results in the formation of highly carbonaceous material due to extensive dehydroflurination (DHF) as well as possibly successive cross-linking in the polymer chains. Upon IL and AA combined solvent treatment, the neat PVDF which composed of both α- and β crystalline phases was transformed to porous and β-phase rich material whereas in case of pure AA the non-porous and pure α-phase polymeric entity was obtained. A combined mixture of IL and AA resulted in a limited the DHF process and subsequent cross-linking in the polymer chains of PVDF allowed the formation of a porous material. It was observed that the porosity of the thermally treated materials was steadily decreasing with increase in the amount of AA in solvents composition and solvent with an AA:IL mole ratio of 2:1 resulted in a PVDF material with the highest porosity amongst the applied solvents. A recovery method for the IL and AA combined solvent after the thermal treatment of PVDF was also established. Hence, with varying the type of solvents in terms of composition, the highly carbonaceous materials as well as materials with different porosities as well as crystalline phases can be obtained. Most importantly here, we introduced new IL and AA containing recoverable solvents for the synthesis of porous PVDF material with the electroactive β-phase.

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  • 7.
    Knutsson, Sofie
    et al.
    Department of Chemistry, Umeå University.
    Kindahl, Tomas
    Department of Chemistry, Umeå University.
    Engdahl, Cecilia
    Department of Chemistry, Umeå University.
    Nikjoo, Dariush
    Department of Chemistry, Umeå University.
    Forsgren, Nina
    CBRN Defence and Security, Swedish Defence Research Agency.
    Kitur, Stanley
    Centre for Biotechnology Research and Development, Kenya Medical Research Institute.
    Ekström, Fredrik
    CBRN Defence and Security, Swedish Defence Research Agency.
    Kamau, Luna
    Centre for Biotechnology Research and Development, Kenya Medical Research Institute.
    Linusson, Anna
    Department of Chemistry, Umeå University.
    N-Aryl-N'-ethyleneaminothioureas effectively inhibit acetylcholinesterase 1 from disease-transmitting mosquitoes2017In: European Journal of Medicinal Chemistry, ISSN 0223-5234, E-ISSN 1768-3254, Vol. 134, p. 415-427Article in journal (Refereed)
    Abstract [en]

    Vector control of disease-transmitting mosquitoes by insecticides has a central role in reducing the number of parasitic- and viral infection cases. The currently used insecticides are efficient, but safety concerns and the development of insecticide-resistant mosquito strains warrant the search for alternative compound classes for vector control. Here, we have designed and synthesized thiourea-based compounds as non-covalent inhibitors of acetylcholinesterase 1 (AChE1) from the mosquitoes Anopheles gambiae (An. gambiae) and Aedes aegypti (Ae. aegypti), as well as a naturally occurring resistant-conferring mutant. The N-aryl-N’-ethyleneaminothioureas proved to be inhibitors of AChE1; the most efficient one showed submicromolar potency. Importantly, the inhibitors exhibited selectivity over the human AChE (hAChE), which is desirable for new insecticides. The structure-activity relationship (SAR) analysis of the thioureas revealed that small changes in the chemical structure had a large effect on inhibition capacity. The thioureas showed to have different SAR when inhibiting AChE1 and hAChE, respectively, enabling an investigation of structure-selectivity relationships. Furthermore, insecticidal activity was demonstrated using adult and larvae An. gambiae and Ae. aegypti mosquitoes.

  • 8.
    Mukesh, Chandrakant
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Mikkola, Jyri-Pekka
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden. Industrial Chemistry & Reaction Engineering, Department of Chemical Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo-Turku, Finland.
    Production of C-14 Levulinate Ester from Glucose Fermentation Liquors Catalyzed by Acidic Ionic Liquids in a Solvent-Free Self-Biphasic System2020In: ACS Omega, E-ISSN 2470-1343, Vol. 5, no 10, p. 4828-4835Article in journal (Refereed)
    Abstract [en]

    Herein, we present the C-14 levulinate ester of 2,3-butanediol as the product of sugar fermentation liquors. The designed Brønsted acidic ionic liquid (BAIL) catalysts enable self-induced phase separation with ester products, and the role of anions has been investigated. Esterification reactions were carried out by 2,3-butanediol (2,3-BDO) and levulinic acid in solvent-free media and low temperatures (60–105 °C). For comparison, sulfuric acid, amberlite IR-120, and sulfonic acid-functionalized pyridinium ionic liquids with different anions were utilized as a catalyst upon esterification reaction. The diester product, namely, butane-2,3-diyl bis(4-oxopentanoate), was formed with a good yield (85%) and selectivity (85%) after complete conversion of 2,3-BDO in 24 h at 80 °C. The low yield (8%) of the monoester was observed. The monoester and diester were separated by a liquid–liquid extraction method. The ester products were characterized by various instrumental techniques such as 1H and 13C NMR, GC–FID, LC–MS, and FT-IR spectroscopy. The Hammett acidity functions of BAILs were determined from UV–vis spectroscopy. The catalyst was successfully recycled and reused in the processes. The spent BAILs were reused in six consecutive cycles with only a ∼7% diminished diester yield and selectivity. The produced levulinate ester will be useful as biofuel additives, solvents, plasticizers, and other applications.

  • 9.
    Mukesh, Chandrakant
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden.
    Sarmad, Shokat
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden.
    Samikannu, Ajaikumar
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Siljebo, William
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden.
    Mikkola, Jyri-Pekka
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90187 Umeå, Sweden; Industrial Chemistry & Reaction Engineering, Department of Chemical Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Åbo-Turku, Finland.
    Pore size-excluded low viscous porous liquids for CO2 sorption at room temperature and thermodynamic modeling study2022In: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 356, article id 119046Article in journal (Refereed)
    Abstract [en]

    Herein, we report porous ionic liquids (type-III) designed to utilize microporous ZIF-8 moieties with functional ionic liquids such as 8-(2-methoxyethyl)-1,8-Diazabicyclo[5.4.0]undec-7-en-8-ium, Bis(trifluoromethane)sulfonamide ([MEDBU][TFSI] and Trioctylammonium 4-para-tert-butylbenzoiate [TOAH][PTBBA]). The prepared materials were thoroughly characterized by means of XRD, FT-IR, SEM, TEM, BET, TGA, DSC and viscometry techniques. The idea of combining the intrinsic properties of ionic liquids with microporous architecture to prepare porous ionic liquids yields promising fluidic materials that have received attention in industrial applications such as gas sorption and separation etc. The prepared porous ionic liquids possess unique physico-chemical properties such as low viscosity, high thermal stability, low vapor pressure, reusability and their fluidic nature renders the materials suitable for CO2 capture. Herein introduced porous ionic liquids (ILs) showed enhanced CO2 uptake (0.92 mmol/g in [TOAH][PTBBA]-Z100 and 1.16 mmol/g in [MEDBU][TFSI]-Z200), or in other words, 15–47% higher sorption capacity compared to neat ionic liquids. This concept overcomes the drawbacks of highly viscous ILs and their limited CO2 sorption capacity. Thermodynamic modeling further demonstrated that the enthalpy of sorption is only −9.99 kJ mol−1, indicating that significantly less energy is required for regeneration. This is promising for the potential use of these fluidic materials in continuous separation processes on an industrial scale, as a better alternative to the existing hazardous amine scrubbing.

  • 10. Nikjoo, Dariush
    Design and Synthesis of a Small Set of Thiourea-based Compounds as Inhibitors of AChE1 from Mosquitoes2014Other (Other academic)
  • 11.
    Nikjoo, Dariush
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Akhtar, Farid
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Porous polymeric membranes as CO2 adsorbents2017Conference paper (Refereed)
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  • 12.
    Nikjoo, Dariush
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Akhtar, Farid
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Structured emulsion-templated porous copolymer based on photopolymerization for carbon capture2017In: Journal of CO2 Utilization, ISSN 2212-9820, E-ISSN 2212-9839, Vol. 21, p. 473-479Article in journal (Refereed)
    Abstract [en]

    Porous hydrogel copolymers of acrylamide (AAM) and acrylic acid (AAC) were structured in the form of monoliths and granules. AAM-co-AAC porous copolymer monoliths were synthesized using high internal phase emulsion (HIPE) as template and photopolymerization. For granulation, photopolymerization was used for the fabrication of the AAM-co-AAC hydrogel, which was subsequently freeze-granulated. The structural analysis (FTIR and XRD) confirmed the successful synthesis of hydrogel copolymers. The CO2 uptake capacity of structured AAM-co-AAC copolymers was evaluated through adsorption and absorption mechanisms by volumetric and gravimetric methods, respectively. The granules exhibited the CO2 adsorption uptake of 0.8 mmol g-1 at 25 kPa and 298 K. The CO2 and N2 adsorption data demonstrated that the hydrogel copolymers were selective for CO2. Furthermore, the granules were capable of capturing CO2 in the presence of water. The results of absorption of CO2 on water-swollen granules demonstrated that CO2-uptake capacity increases with increasing water content up to 1.8 mmol g-1.

  • 13.
    Nikjoo, Dariush
    et al.
    Department of Chemistry, Faculty of Engineering, Istanbul University, Avcilar, Istanbul, 34320, Turkey.
    Aroguz, Ayse Z.
    Department of Chemistry, Faculty of Engineering, Istanbul University, Avcilar, Istanbul, 34320, Turkey.
    Dual responsive polymeric bionanocomposite gel beads for controlled drug release systems2017In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 134, no 33, article id 45143Article in journal (Refereed)
  • 14.
    Nikjoo, Dariush
    et al.
    Department of Chemistry, Faculty of Engineering, Istanbul University, Avcilar, Istanbul, Turkey.
    Aroguz, Ayse Z.
    Department of Chemistry, Faculty of Engineering, Istanbul University, Avcilar, Istanbul, Turkey.
    Magnetic field responsive methylcellulose-polycaprolactone nanocomposite gels for targeted and controlled release of 5-fluorouracil2016In: International Journal of Polymeric Materials, ISSN 0091-4037, E-ISSN 1563-535X, Vol. 65, no 8, p. 421-432Article in journal (Refereed)
  • 15.
    Nikjoo, Dariush
    et al.
    Department of Chemistry, Faculty of Engineering, Istanbul University.
    Aroguz, Ayse Z.
    Department of Chemistry, Faculty of Engineering, Istanbul University.
    Viscometric Analysis of Miscibility and Interactions for Binary, Ternary Polycarbonate/Brominated Polystyrene + Chloroform Systems at Different Temperatures2013In: Journal of macromolecular science. Pure and applied chemistry (Print), ISSN 1060-1325, E-ISSN 1520-5738, Vol. 50, no 9, p. 1007-1011Article in journal (Refereed)
    Abstract [en]

    Viscosities of ternary systems consist of polycarbonate (PC)/brominated polystyrene (PBrS) in chloroform and their corresponding binary systems were measured at different temperatures (20, 25, and 30°C). All the measurements were carried out at the concentration ranges of 0.1–0.6 g·dL−1. The mass ratio of PC to PBrS was selected as 75:25, 50:50, and 25:75 in the ternary solutions. Two empirical expressions of Huggins and Kraemer equations with three-parameters were used for reproducing of the experimental viscosity data. The fitting parameters were obtained for the corresponding temperatures. The miscibility criteria on the basis of the sign of Δ[η]m based on the difference between experimental and ideal values of [η]m, was calculated by applying the Garcia et al., theoretical equation. The effect of temperature on the viscosity data was also studied. The results from this method were correlated with the miscibility data obtained for the same system by differential scanning calorimeter (DSC) findings.

  • 16.
    Nikjoo, Dariush
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Perrot, Virginie
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Akhtar, Farid
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Laminated Porous Diatomite Monoliths for Adsorption of Dyes From Water2019In: Environmental Progress & Sustainable Energy, ISSN 1944-7442, E-ISSN 1944-7450, Vol. 38, no s1, p. 377-385Article in journal (Refereed)
    Abstract [en]

    Structured laminated diatomite monoliths with superior mechanical properties were prepared by controlled freeze-casting of the aqueous suspensions of diatomite powders for wastewater treatment. The directional freezing of suspensions with solids loading of 25, 30, and 37 wt % at cooling from 0.5 to 5 K/min resulted in the formation of lamellar pores and solid walls with the thickness of 12–30 and 14–39 μm, respectively. The increase in solid loading and freezing rate resulted in refinement of the porous structure. Durable monoliths with the mechanical strength of 5.3 MPa were obtained by thermal treatment of the freeze-dried green bodies at 1,373 K. Diatomite monoliths with a pore size of 29.6 μm showed the removal of model dye pollutant Rhodamine B from water by adsorption and long-term water stability. The dye uptake capacity of monolith changed from 1.38 to 17.04 mg/g for the initial dye concentrations between 1.0 and 12.5 mg/L at 298 K and pH = 6, respectively. The adsorption data analysis using Lagergren's pseudo-first-order, pseudo-second-order, and intra-particle diffusion models revealed that diatomite monoliths offered efficient mass transfer in the porous laminated scaffold and to the adsorption sites and bulk diffusion of dye molecules in water was the rate-limiting mechanism for dye removal. © 2018 American Institute of Chemical Engineers Environ Prog, 2018.

  • 17.
    Nikjoo, Dariush
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Pharmaceutical Biosciences, Uppsala University, P.O. Box 591, 75124 Uppsala, Sweden.
    van der Zwaan, Irès
    Department of Pharmaceutical Biosciences, Uppsala University, P.O. Box 591, 75124 Uppsala, Sweden.
    Brülls, Mikael
    Early Product Development & Manufacturing, Pharmaceutical Sciences, R&D, AstraZeneca, 43183 Gothenburg, Sweden.
    Tehler, Ulrika
    Advanced Drug Delivery, Pharmaceutical Sciences, R&D, Astra Zeneca, 43183 Gothenburg, Sweden.
    Frenning, Göran
    Department of Pharmaceutical Biosciences, Uppsala University, P.O. Box 591, 75124 Uppsala, Sweden.
    Hyaluronic Acid Hydrogels for Controlled Pulmonary Drug Delivery—A Particle Engineering Approach2021In: Pharmaceutics, ISSN 1999-4923, E-ISSN 1999-4923, Vol. 13, no 11, article id 1878Article in journal (Refereed)
    Abstract [en]

    Hydrogels warrant attention as a potential material for use in sustained pulmonary drug delivery due to their swelling and mucoadhesive features. Herein, hyaluronic acid (HA) is considered a promising material due to its therapeutic potential, the effect on lung inflammation, and possible utility as an excipient or drug carrier. In this study, the feasibility of using HA hydrogels (without a model drug) to engineer inhalation powders for controlled pulmonary drug delivery was assessed. A combination of chemical crosslinking and spray-drying was proposed as a novel methodology for the preparation of inhalation powders. Different crosslinkers (urea; UR and glutaraldehyde; GA) were exploited in the hydrogel formulation and the obtained powders were subjected to extensive characterization. Compositional analysis of the powders indicated a crosslinked structure of the hydrogels with sufficient thermal stability to withstand spray drying. The obtained microparticles presented a spherical shape with mean diameter particle sizes from 2.3 ± 1.1 to 3.2 ± 2.9 μm. Microparticles formed from HA crosslinked with GA exhibited a reasonable aerosolization performance (fine particle fraction estimated as 28 ± 2%), whereas lower values were obtained for the UR-based formulation. Likewise, swelling and stability in water were larger for GA than for UR, for which the results were very similar to those obtained for native (not crosslinked) HA. In conclusion, microparticles could successfully be produced from crosslinked HA, and the ones crosslinked by GA exhibited superior performance in terms of aerosolization and swelling.

  • 18.
    Nikjoo, Dariush
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Pharmaceutical Biosciences, Uppsala University, P.O. Box 591, 751 24 Uppsala, Sweden.
    van der Zwaan, Irès
    Department of Pharmaceutical Biosciences, Uppsala University, P.O. Box 591, 751 24 Uppsala, Sweden.
    Rudén, Jonas
    Pharmaceutical Development, Orexo AB, 751 05, Uppsala, Sweden.
    Frenning, Göran
    Department of Pharmaceutical Biosciences, Uppsala University, P.O. Box 591, 751 24 Uppsala, Sweden.
    Engineered microparticles of hyaluronic acid hydrogel for controlled pulmonary release of salbutamol sulphate2023In: International Journal of Pharmaceutics, ISSN 0378-5173, E-ISSN 1873-3476, Vol. 643, article id 123225Article in journal (Refereed)
    Abstract [en]

    Most pulmonary drugs are immediate-release formulations with short duration of action. Controlled release systems provide the ability to deliver drugs at a controlled rate, which helps maintain drug concentrations within the therapeutic window for a longer period of time. This study aimed to produce microparticles (MPs) of hyaluronic acid hydrogel (HAGA) loaded with salbutamol sulphate (SS) for controlled release in the lung. The drug-loaded MPs were prepared via spray drying and underwent extensive characterization, which revealed that SS was successfully encapsulated in the HAGA matrix. The prepared MPs (denoted as HASS) ranged in size from 1.6 ± 0.4 μm to 1.7 ± 0.5 μm with a fine particle fraction (FPF) of 48–56% and showed improvement in aerodynamic properties compared to unloaded HAGA hydrogel MPs. In vitro drug release studies performed in a Transwell system confirmed the potential of the particles to release the drug in a sustained manner. The drug release was delayed for all formulations, with a t63 between 5 and 30 min, compared to <1min for pure SS. This study advances our understanding of the formulation of a highly soluble drug to achieve controlled release in the lung.

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  • 19.
    Sarmad, Shokat
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90871 Umeå, Sweden.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Mikkola, Jyri-Pekka
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90871 Umeå, Sweden. Industrial Chemistry & Reaction Engineering, John Gadolin Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, Fl-20500 Åbo-Turku, Finland.
    Amine functionalized deep eutectic solvent for CO2 capture: Measurements and modeling2020In: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 309, article id 113159Article in journal (Refereed)
    Abstract [en]

    Deep eutectic solvents (DESs) have gained a great interest among researchers owing to their inherent advantages to become an adaptable alternative to ionic liquids (ILs) and common amine solutions for CO2 capture. In the present study, we prepared five new three-component DESs by functionalization of choline chloride-ethanolamine (1,7, mol,mol) DES using different types of amines: diethanolamine (amine type 2), methyldiethanolamine (amine type 3), piperazine (amine type 2) as well as 1-(2-aminoethyl)piperazine (amine type 1 and 2). All of the prepared DESs are liquid at room temperature and their melting points were in the range of 265–276 K. The solubility of CO2 in the studied DESs was measured at pressures up to 2 MPa and 298.15 K. The obtained experimental data were analyzed by the use of generic Redlich-Kwong equation of state (RK-EOS) model and Henry's law constant have been calculated from the obtained experimental data through the EOS correlation. All the studied DESs show chemical absorption of CO2 which can be approved based on the excess enthalpy and Gibbs energy functions. FT-IR spectroscopy and 13C NMR verified the formation of carbamate in the CO2 absorption process which revealed the chemisorption of CO2 in the studied DESs. The ideal association model has been utilized to describe the excess thermodynamic functions and two different types of the chemical association have been detected AB2 and AB, (A refer to DESs and B to CO2). Based on the obtained solubility data, the amines that enhanced the absorption capacity of choline chloride-ethanolamine (1,7) follow the trend as follows: piperazine > aminoethylpiperazine > methyldiethanolamine > diethanolamine. Therefore, piperazine can be considered as an absorption enhancer. The viscosity of DESs before and after CO2 absorption as well as the thermal behavior of the DESs were also investigated.

  • 20.
    Sarmad, Shokat
    et al.
    Wallenberg Wood Science Center, Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90871 Umeå, Sweden.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Mikkola, Jyri-Pekka
    Wallenberg Wood Science Center, Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, SE-90871 Umeå, Sweden; Industrial Chemistry & Reaction Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, FI-20500 Åbo-Turku, Finland.
    Innovative CO2 capture technologies: Exploring the potential of porous liquids containing deep eutectic solvents and hypercrosslinked polymers2025In: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 352, article id 128189Article in journal (Refereed)
    Abstract [en]

    The current study presented a porous liquid (PL) prepared from propylene glycol-based deep eutectic solvent (DES) and hyper-crosslinked polymers (HCP) that are liquids over wide temperature ranges, including ambient temperature. It was shown that the solvent molecules are too large to penetrate the pores of HCP, so the PL is maintained as a suspension with permanent free volume for several months and can absorb large amounts of gases. This study marks the pioneering use of DESs as the liquid medium, replacing ionic liquids due to their closely matched properties. The structural features of both DES and HCP are retained; the increase in CO2 absorption capacity compared to pure DES is due to the presence of a porous solid and is proportional to the amount of solid. The absorbed CO2 amount rises from 1.0105 mmol·g−1 in pure DES to 1.3232, 1.6027, and 1.2168 mmol·g−1 in PL-1, PL-2, and PL-3, respectively. Thermodynamic analysis revealed that the enthalpy of gas absorption allows straightforward regeneration of the PLs in the studied cases. The investigated PLs show great potential as gas absorbents, with the incorporation of just 0.5 wt% of porous polymer material leading to an impressive increase in solvent absorption capacity, up to 59 %.

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  • 21.
    Sarmad, Shokat
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, Umeå, Sweden.
    Taghi Zafarani-Moattar, Mohammed
    Physical Chemistry Department, University of Tabriz, Tabriz, Iran.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Mikkola, Jyri-Pekka
    Industrial Chemistry & Reaction Engineering, John Gadolin Process Chemistry Centre, Åbo Akademi University, Turku, Finland.
    How Different Electrolytes Can Influence the Aqueous Solution Behavior of 1-Ethyl-3-Methylimidazolium Chloride: A Volumetric, Viscometric, and Infrared Spectroscopy Approach2020In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, article id 593786Article in journal (Refereed)
    Abstract [en]

    The density, sound velocity, and viscosity of 1-ethyl-3-methylimidazolium chloride [C2mim]Cl in pure water and aqueous solutions of some electrolytes such as potassium chloride, potassium carbonate, and potassium phosphate (weight fraction of salt fixed at ws = 0. 11) have been measured over a wide range of temperatures from 298.15 to 318.15 K. The obtained experimental data have been used to compute various volumetric, compressibility, and viscometric parameters, e.g., apparent molar properties, limiting apparent molar and transfer properties. The co-sphere overlap model was employed to describe the dominant intermolecular interactions in the ternary solutions. Additionally, the structure making/breaking nature of the [C2mim]Cl in the ternary solutions has been discussed in terms of Hepler's constant and the temperature derivative of viscosity B-coefficient (dB/dT). The activation free energy of solvent and solute, activation enthalpy, and activation entropy have been calculated by the application of transition state theory. The calculated parameters have been interpreted in the sense of solvent–solute and solute–solute interactions. The Fourier transform infrared (FTIR) studies also have been done for the studied systems. Volumetric, acoustic, viscometric, and spectroscopic studies can render some evidence and help to understand the aqueous solution behavior of ionic liquids.

  • 22.
    Shukla, Shashi Kant
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, Umeå, Sweden.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Mikkola, Jyri-Pekka
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, Umeå, Sweden. Industrial Chemistry & Reaction Engineering, Department of Chemical, Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Åbo-Turku, Finland.
    Is basicity the sole criterion for attaining high carbon dioxide capture in deep-eutectic solvents?2020In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 22, no 3, p. 966-970Article in journal (Refereed)
    Abstract [en]

    A critical analysis of the role of Hammett basicity (H−) and aqueous basicity (pKa) in CO2 uptake in deep-eutectic solvents (DESs) suggests that neither H− nor pKa correlates with the CO2 w/w% capacity in the studied DESs. Instead, strong “synergistic interactions” between donor and acceptor moieties satisfactorily relate to the w/w% of CO2 in DESs.

  • 23.
    Velaga, Sitaram
    et al.
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Rao Vuddanda, Parameswara
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Drying Kinetics of Polymeric Films: theoretical and experimental studies2016Conference paper (Refereed)
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  • 24.
    Velaga, Sitaram
    et al.
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Rao Vuddanda, Parameswara
    Luleå University of Technology, Department of Health Sciences, Medical Science. Department of Pharmaceutics, UCL School of Pharmacy, University College London.
    Experimental Studies and Modeling of the Drying Kinetics of Multicomponent Polymer Films2018In: AAPS PharmSciTech, E-ISSN 1530-9932, Vol. 19, no 1, p. 425-435Article in journal (Refereed)
    Abstract [en]

    The process of drying thin polymer films is an important operation that influences the film structure and solid state, and the stability of the product. The purpose of this work was to study and model the drying kinetics of multicomponent films based on two polymers: hydroxypropyl methylcellulose (HPMC, amorphous) and polyvinyl alcohol (PVA, semicrystalline). The isothermal drying kinetics of the films at different temperatures (40, 60, and 80°C) were studied using thermo-gravimetric analysis (TGA) and convection oven methods. Solid-state characterization tools used in the study included polarization and hot-stage microscopy, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). The drying kinetics of HPMC and PVA films in the TGA apparatus and convection oven were comparable. The three-parameter (Wmax, τ, n) Hill equation successfully modeled the experimental drying kinetics. The time factor τ in the Hill equation nicely explained two drying phases in the films. Solid-state phase changes occurring in the films during dehydration had a bearing on the drying kinetics and mechanisms. TGA can be used as a simple tool to determine the end points in drying processes using ovens or tunnels. The three-parameter Hill equation explained the drying kinetics and diffusion mechanisms of the solvent through the polymer films for the first time. This study advances our understanding of film drying, in particular for pharmaceutically relevant thin films.

  • 25.
    Velarde, Lisbania
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Chemistry, Faculty of Science and Technology, Universidad Mayor de San Simón, UMSS, Cochabamba, Bolivia.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Escalera, Edwin
    Department of Chemistry, Faculty of Science and Technology, Universidad Mayor de San Simón, UMSS, Cochabamba, Bolivia.
    Akhtar, Farid
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Bolivian natural zeolite as a low-cost adsorbent for the adsorption of cadmium: Isotherms and kinetics2024In: Heliyon, E-ISSN 2405-8440, Vol. 10, no 1, article id e24006Article in journal (Refereed)
    Abstract [en]

    Population growth in recent years has led to increased wastewater production and pollution of water resources. This situation also heavily affects Bolivia, so wastewater treatment methods and materials suitable for Bolivian society should be explored. This study investigated the natural Bolivian Zeolite (BZ) and its NaCl-modified structure (NaBZ) as adsorbents for cadmium removal from water. The natural BZ and the modified form NaBZ were investigated by different physicochemical characterization techniques. Furthermore, XPS and FT-IR techniques were used to investigate the adsorption mechanisms. The cadmium adsorption on BZ and NaBZ was analyzed using various mathematical models, and the Langmuir model provided a better description of the experimental adsorption data with cadmium adsorption capacities of 20.2 and 25.6 mg/g for BZ and NaBZ, respectively. The adsorption followed the pseudo-second order kinetics. The effect of different parameters, such as initial cadmium concentration and pH on the adsorption was studied. In addition, the results of the regeneration test indicated that both BZ and NaBZ can be regenerated by using hydrochloric acid (HCl). Finally, the adsorption experiment of BZ and NaBZ on a real water sample (brine from Salar de Uyuni salt flat) containing a mixture of different heavy metals was carried out. The results obtained in this study demonstrate the effectiveness of natural BZ and modified NaBZ in the removal of heavy metals from wastewater.

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  • 26.
    Zafarani-Moattar, Mohammed Taghi
    et al.
    Physical Chemistry Department, University of Tabriz, Iran.
    Nikjoo, Dariush
    Physical Chemistry Department, University of Tabriz, Iran.
    Liquid−Liquid and Liquid−Liquid−Solid Equilibrium of the Poly(ethylene glycol) Dimethyl Ether 2000 + Sodium Sulfate + Water System2008In: Journal of Chemical and Engineering Data, ISSN 0021-9568, E-ISSN 1520-5134, Vol. 53, no 11, p. 2666-2670Article in journal (Refereed)
    Abstract [en]

    The phase diagram for the poly(ethylene glycol) dimethyl ether (PEGDE) + Na2SO4 + H2O system at 298.15 K using PEGDE with a molar mass of 2000 was determined. Compositions of the liquid−liquid and the liquid−liquid−solid equilibria were determined using calibration curves of refractive index of the solutions, and atomic absorption (AA) and X-ray diffraction analyses were made on the solids. The solid phase in equilibrium with the biphasic region was anhydrous Na2SO4. An empirical nonlinear three-parameter expression developed by Merchuk was used for reproducing the experimental binodal data at T = (288.15, 298.15, 308.15, and 318.15) K, and the fitting parameters were obtained for the corresponding temperatures. The effects of temperature on the binodal curve were also studied, and it was observed that the area of the biphasic region increased slightly with an increase in temperature. The experimental tie-line compositions at the aforementioned temperatures were fitted to both the Othmer−Tobias and Bancroft and Setschenow-type equations. Correlation coefficients for all equations are reported.

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