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  • 1.
    Abbasi, M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Backstrom, J.
    Mid Sweden Univ, FSCN Mat Phys, Dept Nat Sci, SE-85170 Sundsvall, Sweden..
    Cornell, Ann M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Fabrication of Spin-Coated Ti/TiHx/Ni-Sb-SnO2 Electrode: Stability and Electrocatalytic Activity2018In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 165, no 9, p. H568-H574Article in journal (Refereed)
    Abstract [en]

    A novel three-layer anode having the composition Ti/TiHx/Ni-Sb-SnO2 (Ti/TiHx/NATO) was successfully prepared by a spin-coating and pyrolysis process aiming at a long service lifetime and good electrocatalytic properties for ozone formation. The TiHx as an interlayer was produced by electrochemical cathodic reduction of a coated layer of the TiOx on the titanium substrate. Spin coating and thermal decomposition were used to deposit the Sn-Sb-Ni precursor on the surface of the prepared Ti/TiHx electrode. Cyclic and linear scanning voltammetry, Raman spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to reveal the electrode performance and morphology. Results show that the onset potential for the oxygen evolution reaction (OER) of Ti/TiHx /NATO is higher than for Ti/NATO. They also indicate that the service lifetime of the Ti/TiHx/NATO is twice as long as the Ti/NATO at a current density of 50 mA.cm(-2) at room temperature. Electrochemical ozone generation and degradation of the methylene blue were investigated to confirm selectivity and activity of the electrodes. After 5 min electrolysis, a current efficiency for ozone generation of 56% was obtained the electrode with TiHx while 38% was obtained on Ti/NATO under same conditions. The results also confirm that the Ti/TiH x /NATO has a higher kinetic rate constant and decolorization efficiency for removal of the methylene blue compare to the Ti/NATO. The rate constant for the pseudo-first ordered reaction of methylene blue degradation showed high values of 350 x 10(-3) min(-1) for Ti/NATO and 440 x 10(-3) min(-1) for Ti/TiHx/NATO. 

  • 2.
    Abdalla, Abdulbasit
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Odgren, Emilia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Biodiesel production from rape seed oil catalyzed by calcium oxide doped with lithium2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Biodiesel ses som ett av de främsta substituten för fossila bränslen, då den relativt enkelt kan appliceras i redan existerande dieselmotorer. Dagens produktion av biodiesel använder sig av homogena katalysatorer som inte återanvänds i processen, men för en mer cirkulär och i längden en billigare process ses heterogena katalysatorer som ett alternativ. Syftet med denna studie var att undersöka litium dopad kalciumoxid katalytiska egenskaper, de optimala förhållandena för reaktionen och även kinetiken för reaktionen. Den valda katalysatorn syntetiserades med kalcinering och sedan testades den katalytiska förmågan i reaktionen vid olika reaktionsförhållanden, för att finna de optimala förhållandena. Även katalysatorns fysiska egenskaper analyserades och kinetiken för reaktionen. De optimala förhållanden för transesterifieringen bestämdes till 3 h, 1:6 olja- metanolförhållande, 60°C och 5 vikts% katalysator, där 96% utbyte av biodiesel uppnåddes. Övriga utbyten från de andra försöken var betydligt lägre, vilket kan bero på icke optimala förhållanden, men även relativ dålig katalytisk förmåga. Ytarea och porstorlek konstateras vara små, vilket påverkar den katalytiska förmågan negativt. Anledningen till katalysatorns egenskaper beror huvudsakligen på tillverkningsprocessen, men även mängden litium i dopningen. Kinetiken visar en oväntad reaktionsutveckling med initialt hög koncentration FAME (Fatty acid Methylester), vilket troligen beror på felkällor.

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  • 3.
    Abdel-Magied, Ahmed Fawzy
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery. Nuclear Materials Authority. P. O. Box 530, El Maadi, Cairo, Egypt.
    Abdelhamid, Hani Nasser
    Assiut University.
    Ashour, Radwa M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery. Nuclear Materials Authority. P. O. Box 530, El Maadi, Cairo, Egypt.
    Fu, Le
    Central South University.
    Dowaidar, Moataz
    King Fahd University of Petroleum and Minerals (KFUPM).
    Xia, Wei
    Uppsala University.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Magnetic Metal-Organic Frameworks for Efficient Removal of Cadmium(II), and Lead(II) from Aqueous Solution2022In: Journal of Environmental Chemical Engineering, ISSN 2213-3437, p. 107467-107467, article id 107467Article in journal (Refereed)
    Abstract [en]

    Efficient and convenient methods for the removal of toxic heavy metal ions especially Cd(II) and Pb(II) from aqueous solutions is of great importance due to their serious threat to public health and the ecological system. In this study, two magnetic metal-organic frameworks (namily: Fe3O4@ZIF-8, and Fe3O4@UiO-66–NH2) were synthesized, fully characterized, and applied for the adsorption of Cd(II) and Pb(II) from aqueous solutions. The adsorption efficiencies for the prepared nanocomposites are strongly dependent on the pH of the aqueous solution. The maximum adsorption capacities of Fe3O4@UiO-66–NH2, and Fe3O4@ZIF-8 at pH 6.0 were calculated to be 714.3 mg·g 1, and 370 mg·g 1 for Cd(II), respectively, and 833.3 mg·g 1, and 666.7 mg·g 1 for Pb(II), respectively. The adsorption process follows a pseudo-second-order model and fit the Langmuir isotherm model. Moreover, the thermodynamic studies revealed that the adsorption process is endothermic, and spontaneous in nature. A plausible adsorption mechanism was discussed in detail. The magnetic adsorbents: Fe3O4@ZIF-8, and Fe3O4@UiO-66–NH2 showed excellent reusability, maintaining the same efficiency for at least four consecutive cycles. These results reveal the potential use of magnetic Fe3O4@ZIF-8, and Fe3O4@UiO-66–NH2 as efficient adsorbents in removing Cd(II) and Pb(II) from aqueous solutions.

  • 4.
    Abdel-Magied, Ahmed Fawzy
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Nasser Abdelhamid, Hani
    Ashour, Radwa M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Zou, Xiaodong
    Stockholms Universitet.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Hierarchical porous zeolitic imidazolate framework nanoparticles for efficient adsorption of rare-earth elements2019In: Microporous and Mesoporous Materials, ISSN 1387-1811, E-ISSN 1873-3093, Vol. 278, p. 175-184Article in journal (Refereed)
    Abstract [en]

    Hierarchical porous zeolitic imidazolate frameworks nanoparticles (ZIF-8 NPs) were synthesized at room temperature via a template-free approach under dynamic conditions (stirring) using water as a solvent. The ZIF-8 NPs were evaluated as adsorbents for rare earth elements (La3+, Sm3+ and Dy3+). Adsorption equilibrium was reached after 7h and high adsorption capacities were obtained for dysprosium and samarium (430.4 and 281.1 mg g(-1), respectively) and moderate adsorption capacity for lanthanum (28.8 mg g(-1)) at a pH of 7.0. The high adsorption capacitiese, as well as the high stability of ZIF-8 NPs, make the hierarchical ZIF-8 materials as an efficient adsorbent for the recovery of La3+, Sm3+ and Dy3+ from aqueous solution.

  • 5.
    Acevedo Gomez, Yasna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    On Gas Contaminants, and Bipolar Plates in Proton Exchange Membrane Fuel Cells2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The proton exchange membrane (PEM) fuel cell is an electrochemical device that converts chemical energy into electrical energy through two electrocatalytic reactions. The most common catalyst used is platinum on carbon (Pt/C), which has shown the best performance in the fuel cell until now. However, the drawback of this catalyst is that it does not tolerate impurities, and both hydrogen and oxygen may carry small amounts of impurities depending on the production sources. The purpose of this thesis is to understand the effect of two impurities that are less investigated, i.e., ammonia, which may accompany the hydrogen rich reformates from renewable sources, and nitrogen dioxide, which may come from air pollution. The mechanism of contamination and an adequate recovery method for the respective contaminant are studied. Additionally, electroplated bipolar plates with Ni-Mo and Ni-Mo-P coatings were tested as alternatives to stainless steel and carbon materials.

    The results show that ammonia not only provokes changes in the polymer membrane but also in the oxygen reduction reaction (ORR), hydrogen oxidation reaction (HOR) and catalyst ionomer in both electrodes. The extent of performance recovery after the contamination depends on the concentration used and the exposure time. In contrast, nitrogen dioxide affects the catalyst in the electrode directly; the contamination is related to side reactions that are produced on the catalyst’s surface. However, NO2 is not attached strongly to the catalyst and it is possible to restore the performance by using clean air. The time the recovery process takes depends on the potential applied and the air flow.

    Finally, the evaluation of electroplated Ni-Mo and Ni-Mo-P on stainless steel by ex situ and in situ studies shows that these coatings reduce the internal contact resistance (ICR) and the corrosion rate of the stainless steel considerably. However, the in situ experiments show that phosphorus addition to the coating does not improve the fuel cell performance; thus, the Ni-Mo alloy is found to be a promising choice for electroplating stainless steel bipolar plates.

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  • 6.
    Acevedo Gomez, Yasna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lagergren, Carina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Effect of nitrogen dioxide impurities on PEM fuel cell performanceManuscript (preprint) (Other academic)
    Abstract [en]

    Air is the most practical and economical oxidant to feed to the cathode in a proton exchange membrane fuel cell (PEMFC). However, the air is accompanied by small amounts of impurities that affect the performance of the fuel cell. Among these, nitrogen dioxide is the impurity that has been least investigated, and its effect is not fully understood. In this study, a possible mechanism is proposed based on the contamination of the fuel cell at different concentrations and adsorption potentials, and by employing stripping cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The results at different concentrations showed that the catalyst sites are blocked by the adsorption of NO2, and that there is a non-linear relationship between the concentration and degradation. The degradation is suggested to be related to the formation of intermediate species, as also shown by the pseudo-inductive impedance at the concentration of 100 and 200 ppm. Furthermore, the cyclic voltammetry showed that there is an oxidation to NO3- at 1.05 V, followed by the reduction of this specie to NO2- at 0.68 V, and a subsequent reduction of NO2- to N2O and/or NH2OH.

  • 7.
    Acevedo Gomez, Yasna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lagergren, Carina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Performance recovery after contamination with nitrogen dioxide in a PEM fuel cellManuscript (preprint) (Other academic)
    Abstract [en]

    While the market of fuel cell vehicles is increasing, these vehicles will still coexist with combustion engine vehicles on the roads and will be exposed to an environment with significant amounts of contaminants that will decrease the durability of the fuel cell. In order to investigate different recovery methods, a PEM fuel cell is in this study contaminated with 100 ppm of NO2 at the cathode side. The possibility to recover the cell performance is studied by using different airflow rates, different current densities, and by subjecting the cell to successive polarization curves. The results show that the successive polarization curves are the best choice for recovery; it took 35 min to reach full recovery of cell performance, compared to 4.5 hours of recovery with pure air at 0.5 A cm-2 and 110 ml min-1. However, the performance recovery at a current density of 0.2 A cm-2 and air flow 275 ml min-1 was done in 66 min, which is also a possible alternative. Additionally, two operation techniques are suggested and compared during 7 h of operation; air recovery and air depletion. The air recovery technique shows to be a better choice than the air depletion technique.

  • 8.
    Acevedo Gomez, Yasna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lagergren, Carina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Performance Recovery after Contamination with Nitrogen Dioxide in a PEM Fuel Cell2020In: Molecules, ISSN 1431-5157, E-ISSN 1420-3049, Vol. 25, no 5, article id 1115Article in journal (Refereed)
    Abstract [en]

    While the market for fuel cell vehicles is increasing, these vehicles will still coexist with combustion engine vehicles on the roads and will be exposed to an environment with significant amounts of contaminants that will decrease the durability of the fuel cell. To investigate different recovery methods, in this study, a PEM fuel cell was contaminated with 100 ppm of NO2 at the cathode side. The possibility to recover the cell performance was studied by using different airflow rates, different current densities, and by subjecting the cell to successive polarization curves. The results show that the successive polarization curves are the best choice for recovery; it took 35 min to reach full recovery of cell performance, compared to 4.5 h of recovery with pure air at 0.5 A cm(-2) and 110 mL min(-1). However, the performance recovery at a current density of 0.2 A cm(-2) and air flow 275 mL min(-1) was done in 66 min, which is also a possible alternative. Additionally, two operation techniques were suggested and compared during 7 h of operation: air recovery and air depletion. The air recovery technique was shown to be a better choice than the air depletion technique.

  • 9.
    Adolfsson, Erik
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Future-competing battery chemistries for large-scale energy storage2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With net-zero emissions set to be achieved in the EU by 2050, the transition from fossil-based energy sources to more renewable and green options are ever expanding. This puts a strain on the electricity grids because of the intermittent nature from these energy sources. To mitigate this battery systems are used, of which the lithium-ion battery is the most prevalent, and expected to only increase in use. However, material resource concerns and possible danger of over-reliance on one technology has opened for a search to find other alternatives that could be used instead or in conjunction with the battery. Out of a long list of batteries, the nickel-hydrogen battery, zinc-bromide flow battery and iron-air battery are three alternatives that have been identified to have potential. Their suitability was researched and discussed for various grid-applications. The result show that out of the three, it is only believed that the nickel-hydrogen battery have a definitive competitiveness, that the zinc bromide flow battery has few things going for it, and that the iron-air battery has large potential but just as large uncertainty surrounding its future. Lastly, a specific off-shore wind park case was investigated to see the practicality and competitiveness of the nickel-hydrogen battery compared to a specific lithium-ion chemistry.

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  • 10.
    Af Ugglas, Samuel
    et al.
    Scania CV AB, Scania CV AB.
    Vlasenko, Tayisiya
    Scania CV AB, Scania CV AB.
    Ersson, Anders
    Scania CV AB, Scania CV AB.
    Pettersson, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Process Technology.
    Kusar, Henrik
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Process Technology.
    Reactivity of Diesel Soot from 6- and 8-Cylinder Heavy-Duty Engines2023Conference paper (Refereed)
    Abstract [en]

    Increasing concern for air pollution together with the introduction of new types of fuels pose new challenges to the exhaust aftertreatment system for heavy-duty (HD) vehicles. For diesel-powered engines, emissions of particulate matter (PM) is one of the main drawbacks due to its effect on health. To mitigate the tailpipe emissions of PM, heavy-duty vehicles are since Euro V equipped with a diesel particulate filter (DPF). The accumulation of particles causes flow restriction resulting in fuel penalties and decreased vehicle performance. Understanding the properties of PM produced during engine operation is important for the development and optimized control of the DPF. This study has focused on assessing the reactivity of the PM by measuring the oxidation kinetics of the carbonaceous fraction. PM was sampled from two different heavy-duty engines during various test cycles. The heavy-duty engines were 6- and 8-cylinder direct injection diesel engines rated at 550 and 650 hp respectively. Reaction kinetics of the samples and characteristic oxidation temperatures were assessed by the non-isothermal thermogravimetric analysis (TGA) employing a multiple-ramp rates method in a 10% oxygen atmosphere. The oxidation of the diesel soot was compared with a model soot, Printex-U, and values were compared with the existing literature. The calculated activation energies range between 114.8 and 155.8 kJ/mol for diesel soot as well as the Printex-U samples indicating similar reactivity despite differences in engine configuration, fuel chemistry or, aging.

  • 11.
    Agarwal, Ayush
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Experimental study of high-pressure fluidized bed gasification of biomass at pilot scale: A proof of concept2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Climate change is real. Rising world population and increasing energy demands are taking a toll on the planet. Moving towards a greener, cooler and sustainable future, there is a need for cleaner, efficient, and reliable sources of energy, and biomass is one of them. This thesis work performed at KTH Royal Institute of Technology attempts to contribute to this pressing need. High-pressure biomass gasification technology is an important process intensification step. However, it is not well investigated yet. This work attempts to understand the performance and pave the pathway for future studies.

    Experiments were performed using olivine, magnesite, and silica sand as bed material. Grot and birch were tested as fuel. The experiments were carried out in a 75 KWfuel bubbling fluidized bed gasifier at 20 bar, using Steam/Oxygen as a gasifying agent. Produced gas composition, tar production, and carbon conversion efficiency were examined. Olivine and magnesite showed good resistance against attrition and agglomeration. Stable bed temperature with no signs of defluidization or sintering were observed during the experiments. Silica sand cannot be used as a bed material with grot due to its high ash content. However, mild agglomeration was also observed with the birch feedstock. Carbon dioxide in the produced gas increased with increase in pressure, whereas, carbon monoxide decreased with increase in pressure. Olivine showed excellent reduction properties for tars lighter than naphthalene, whereas, magnesite performed best for overall tar reduction for grot. It was observed that fuel feeding is a big challenge for running operation at high pressure.

    These tests at 20 bar were an intermediate step to validate BFB biomass gasification at 40 bar. It would be interesting to study the changes in gas composition, tar, and char formation to evaluate the performance related to carbon conversion efficiency, produced gas composition, and tar production for different bed material at 40 bar.

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  • 12.
    Agredano Torres, Manuel
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electric Power and Energy Systems.
    Xu, Qianwen
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electric Power and Energy Systems.
    Zhang, Mengfan
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electric Power and Energy Systems.
    Söder, Lennart
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electric Power and Energy Systems.
    Cornell, Ann M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Dynamic power allocation control for frequency regulation using hybrid electrolyzer systems2023In: 2023 IEEE Applied Power Electronics Conference And Exposition, APEC, Institute of Electrical and Electronics Engineers (IEEE) , 2023, p. 2991-2998Conference paper (Refereed)
    Abstract [en]

    The increase in hydrogen production to support the energy transition in different sectors, such as the steel industry, leads to the utilization of large scale electrolyzers. These electrolyzers have the ability to become a fundamental tool for grid stability providing grid services, especially frequency regulation, for power grids with a high share of renewable energy sources. Alkaline electrolyzers (AELs) have low cost and long lifetime, but their slow dynamics make them unsuitable for fast frequency regulation, especially in case of contingencies. Proton Exchange Membrane electrolyzers (PEMELs) have fast dynamic response to provide grid services, but they have higher costs. This paper proposes a dynamic power allocation control strategy for hybrid electrolyzer systems to provide frequency regulation with reduced cost, making use of advantages of AELs and PEMELs. Simulations and experiments are conducted to verify the proposed control strategy.

  • 13.
    Ahlén Norberg, Evelina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Influence of current harmonics on the degradation of the catalyst coated membrane in PEMFC2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The marine shipping industry is dominated by fossil fuel driven propulsion. Electrification of marine vessels is one of the main strategies to enable emission-free propulsion. Hydrogen is an excellent energy carrier to meet the power demand of a marine vessel. Proton exchange membrane fuel cells (PEMFC) is a commercially available alternative for converting hydrogen into electricity. However, durability issues of the PEMFC is a constraint with the technology which limits technical lifetime. Research around ripple currents impact on degradation of PEMFC is scarce and the reported results are ambiguous and lack clear correlation between the effects of the ripple current on the lifetime of a PEMFC.

    This master thesis evaluates the impact on degradation of a single cell PEMFC by imposing a sinusoidal (70 Hz, 50 % amplitude) AC ripple to a dynamic load cycle. The dynamic load cycle is designed to simulate typical operating conditions of a marine vessel. Constant load cycling at 0.4 A/cm2 with the same ripple characteristics was also conducted to verify the dynamic load cycling impact on the performance losses of the PEMFC.

    The in-situ characterization showed performance losses both during the dynamic and constant load cycling, for the ripple current and reference tests. To conclude, no significant effects on degradation by the sinusoidal ripple current of 70 Hz and 50% amplitude is found when applied to a single cell PEMFC despite of performance losses for all cases.

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  • 14.
    Ahmed, Safiya
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Carlsson, Jesper
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Blomberg, Jenny
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Wiberg, Filip
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Biokol av avfallsfraktioner från IKEA:s möbeltillverkning2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I dagens samhälle genereras en stor mängd avfall, där stora delar av avfallen förbränns vilket inte är gynnsamt för vare sig miljön eller klimatet. Därför finns det idag ett stort behov av klimatsmarta metoder där avfallen kan användas till att producera produkter som kan motverka klimatförändringar. Största delen av avfallen som genereras kommer från större företag som till exempel IKEA och de är i ständigt behov av nya metoder för att kunna använda sina avfall till klimatsmarta resurser. Att producera biokol av avfallen är en sådan klimatsmart metod, där biokolet är en hållbar produkt som både motverkar klimatförändringar och andra miljöproblem såsom övergödning. I denna rapport undersöktes två avfallsfraktioner från IKEA, vilka var Dust2k och Hogger. Det som undersöktes var hur lämpliga avfallsfraktionerna från IKEA är för produktion av biokol som skulle kunna appliceras i jordbruket samt hur denna lämplighet påverkas av avfallsfraktion och processförhållanden som används under pyrolysen.

    För att besvara frågeställningarna utfördes pyrolys på avfallsfraktionerna vid pyrolystemperaturerna 550℃ och 750℃, vilket gav fyra olika prover av biokol. Dessa prov analyserades med ett antal analysmetoder för att avgöra biokolets lämplighet som jordförbättrare och för att motverka klimatförändringar. De analyser som utfördes var elementaranalys, pH-mätning, termogravimetrisk analys (TGA), Brunauer-Emmet-Teller (BET) och svepelektronmikroskopi (SEM). Från pyrolysen och TGA kunde utbytet bestämmas, vilket uppgick till över 20% för samtliga prov. Elementaranalysen visade att biokol producerat av Hogger vid 900°C uppfyllde de EBC-krav som analyserades. Genom att mäta pH på avfallsfraktionerna samt biokolen gick det att se att pH höjdes under pyrolysen. Från BET och SEM erhölls information om porositet, ledningsförmåga och ytarea. Porositeten ökade med temperaturen och ledningsförmågan var högre för biokolet än biomassan. Ytarean låg mellan 347,2 m2/g och 422,8 m2/g och porvolymen mellan 0,173 cm3/g och 0,205 cm3/g. Det erhölls bäst egenskaper för avfallsfraktionen Hogger samt pyrolystemperaturen 750℃, vilket gjorde att slutsatsen att produktion av biokol från Hogger vid 750℃ lämpar sig bäst för användning som jordförbättrare kunde dras.

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  • 15.
    Ahuja, Dipali
    et al.
    Univ Limerick, Dept Chem Sci, SFI Res Ctr Pharmaceut, Bernal Inst,SSPC, Castletroy, Co Limerick, Ireland..
    Svärd, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Lusi, Matteo
    Univ Limerick, Dept Chem Sci, SFI Res Ctr Pharmaceut, Bernal Inst,SSPC, Castletroy, Co Limerick, Ireland..
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena. Univ Limerick, Dept Chem Sci, SFI Res Ctr Pharmaceut, Bernal Inst,SSPC, Castletroy, Co Limerick, Ireland..
    Solution and calorimetric thermodynamic study of a new 1:1 sulfamethazine-3-methylsalicylic acid co-crystal2020In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 22, no 20, p. 3463-3473Article in journal (Refereed)
    Abstract [en]

    A new 1:1 co-crystal of sulfamethazine (API, SMT) and 3-methylsalicylic acid (coformer, 3mSA) has been synthesized and its crystal structure solved by single crystal X-ray diffraction (XRD). The co-crystal has been thoroughly characterized by powder XRD, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The pure co-crystal could be synthesized by solvent drop grinding, cooling crystallization and slurry conversion co-crystallization. Ternary phase diagrams have been constructed in methanol and acetonitrile at 30 degrees C. The co-crystal exhibits incongruent dissolution in both solvents. The thermodynamics of co-crystal formation have been estimated from solubility data and calorimetric data, respectively, showing that formation of the SMT-3mSA co-crystal from its solid components is spontaneous and entropy-driven. The co-crystal formation is associated with a 5% increase in molecular volume. A relationship between the size of the region where the co-crystal is the most stable solid phase and the relative solubility of the co-crystal components has been uncovered. The co-crystal region becomes smaller as the solubility ratio increases.

  • 16.
    Ahuja, Dipali
    et al.
    Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Castletroy, Co Limerick, Ireland..
    Svärd, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena. Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Castletroy, Co Limerick, Ireland..
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena. Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Castletroy, Co Limerick, Ireland..
    Investigation of solid-liquid phase diagrams of the sulfamethazine-salicylic acid co-crystal2019In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 21, no 18, p. 2863-2874Article in journal (Refereed)
    Abstract [en]

    The influence of temperature and solvent on the solid-liquid phase diagram of the 1 : 1 sulfamethazinesalicylic acid co-crystal has been investigated. Ternary phase diagrams of this co-crystal system have been constructed in three solvents: methanol, acetonitrile and a 7 : 3 (v/v) dimethylsulfoxide-methanol mixture, at three temperatures. The system exhibits congruent dissolution in acetonitrile and the co-crystal solubility has been determined by a gravimetric technique. The Gibbs energy of co-crystal formation from the respective solid components has been estimated from solubility data, together with the corresponding enthalpic and entropic component terms. The Gibbs energy of formation ranges from -5.7 to -7.7 kJ mol -1, with the stability increasing with temperature. In methanol and the DMSO-methanol mixture, the co-crystal dissolves incongruently. It is shown that the solubility ratio of the pure components cannot be used to predict with confidence whether the co-crystal will dissolve congruently or incongruently. The size of the region where the co-crystal is the only stable solid phase is inversely related to the pure component solubility ratio of salicylic acid and sulfamethazine.

  • 17.
    Aisling, Lynch
    et al.
    Univ Limerick, Synth & Solid State Pharmaceut Ctr, Mat & Surface Sci Inst, Dept Chem & Environm Sci, Limerick, Ireland..
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering. Synthesis and Solid State Pharmaceutical Centre, Department of Chemical and Environmental Science, University of Limerick, Limerick, Ireland.
    Crystal Growth of Single Salicylamide Crystals2019In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 19, no 12, p. 7230-7239Article in journal (Refereed)
    Abstract [en]

    Growth of single salicylamide crystals was investigated in a nonstirred growth cuvette and on a rotating disk. In the growth cuvette the crystal growth rates were measured for both primary nucleated crystals and seed crystals manually inserted into the cuvette. In the rotating disk experiments multiple seed crystals were attached to a disk that was rotated in a supersaturated solution. The crystal growth rates in the length and width direction were precisely measured in situ for each individual crystal, and growth rates were also extracted for a specific crystal facet, that is, (200). In all cases, the growth rate was considerably faster in the rotating disk experiments, shown to be governed by surface integration. Solvent was found to impact the growth rates of the crystal facets in part by creating different surface features. The influence of the supersaturation on the crystal growth rate depended on the solvent; in general, an increasing trend was observed. At relatively low supersaturations, it was discovered that the growth process will focus on repairing morphological defects. Within the range of experimental conditions, the growth kinetics were strongly affected by the temperature as was further indicated by the relatively high activation energy values obtained. The crystal seed quality was found to have a substantial impact on the growth rate, with rougher crystals leading to quicker growth. A wide growth rate dispersion was obtained for both crystal growth methods, found to be reduced by using seed crystals with high quality, lower supersaturations, and also within certain solvents.

  • 18.
    Ajpi, Cesario
    et al.
    UMSA, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz, Bolivia..
    Suescun, Leopoldo
    Univ Republica, Fac Quim, Cryssmat Lab DETEMA, Montevideo, Uruguay..
    Leiva, Naviana
    UMSA, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz, Bolivia..
    Lundblad, Anders
    Res Inst Sweden, RISE, Div Safety & Transport Elect, SE-50462 Boras, Sweden..
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Cabrera, Saul
    UMSA, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz, Bolivia..
    Crystal structure and Hirshfeld surface analysis of poly[tris(mu(4)-benzene-1,4-dicarboxylato)tetrakis(di-methylformamide)tr inickel(II)]: a two-dimensional coordination network2019In: Acta Crystallographica Section E: Crystallographic Communications, ISSN 2056-9890, Vol. 75, p. 1839-1843Article in journal (Refereed)
    Abstract [en]

    The crystal structure of the title compound, [Ni-3(C8H4O4)(3)(C3H7NO)(4)], is a two-dimensional coordination network formed by trinuclear linear Ni-3(tp)(3)(DMF)(4) units (tp = terephthalate = benzene-1,4-dicarboxylate and DMF = dimethyl-formamide) displaying a characteristic coordination mode of acetate groups in polynuclear metal-organic compounds. Individual trinuclear units are connected through tp anions in a triangular network that forms layers. One of the DMF ligands points outwards and provides interactions with equivalent planes above and below, leaving the second ligand in a structural void much larger than the DMF molecule, which shows positional disorder. Parallel planes are connected mainly through weak C-H center dot center dot center dot O, H center dot center dot center dot H and H center dot center dot center dot C interactions between DMF molecules, as shown by Hirshfeld surface analysis.

  • 19.
    Ajpi Condori, Cesario
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry. UMSA-University.
    Hybrid materials for lithium-ion batteries2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Lithium‐ion batteries are the most important power source for electronic devices as electronics, storage and the different electric vehicles. The research and development of new materials for different applications has increased, especially in the development of materials with better electrochemical properties (Specific capacity, rate capability, high energy density and cyclability). Inorganic materials such as LiFePO4, LiMn2O4 and organic materials such as Li4C6O6, quinones and anthraquinones, polyaniline (PANI) and others have been extensively studied. Improvement of the electrochemical properties involve different aspects as: control in the particle size of the materials, doping with other elements and the combination of the different properties of the organic an inorganic materials. The development of hybrids materials with improved electrochemical properties need a combination between of inorganic and organic structures. This type of hybrids materials are a very attractive option for the development of advanced materials. For the design of this type of hybrid materials it is necessary to form interactions between the inorganic and organic part (supramolecular chemistry). This opens up for using an immense amount of organic materials such as conductive polymers and PANI (Polyaniline) are attractive alternatives in the development of hybrid materials due to their excellent electronic conductivity. Other attractive types of hybrid materials are compounds based on metal-organic frameworks (MOF), coordination polymers (CP) and coordination networks (CN).

    This thesis work is focused in the synthesis, structural characterization and electrochemical characterization of two groups of hybrid materials: 

    1) LiFePO4-PANI synthetized by different methods.

    2) Metal-organic compounds M-BDC-DMF with M=Ni2+, Fe2+, C8H4O2=Terephthalate=BDC=Benzene dicarboxylate, DMF=N,N-dimethylformamide.

    The materials were synthesized by chemical oxidation methods combined with thermal treatment (LiFePO4-PANI-Li hybrid powder) and by solvothermal methods (M-BDC-DMF). The materials were characterized by SCXRD, PXRD, FTIR, SEM and electrochemical methods and the electrochemical characterization was carried out using CV, EIS and galvanostatics methods. 

    The specific capacities of PANI was 95 mAh/g, of LiFePO4 was 120 mAh/g and of LiFePO4-PANI was 145 mAh/g at 0.1C. At 2C the capacity of LiFePO4 was 70 mAh/g and LiFePO4-PANI was 100 mAh/g. The specific capacities of Ni3(C8H4O4)3(C3H7NO)4 is ~50 mAh/g and Fe-BDC-DMF was ~175 mAh/g. 

    The work has shown that PANI can improve the performance of LFP also at higher discharges rates. For M-BDC-DMF stability seems to be an issue which should be studied more in the future.

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  • 20.
    Ajpi Condori, Cesario
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry. UMSA-University.
    Leiva, Naviana
    Lundblad, Anders
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Cabrera, Saul
    Synthesis and spectroscopic characterization of Fe3+-BDC metal organic framework as material for lithium ion batteries2023In: Journal of Molecular Structure, ISSN 0022-2860, E-ISSN 1872-8014, Vol. 1272, p. 134127-134127, article id 134127Article in journal (Refereed)
    Abstract [en]

    This work presents synthesis and spectroscopic characterization of a new metal-organic framework (MOF). The compound Fe-BDC-DMF was synthetized by the solvothermal method and prepared via a reaction between FeCl3.6H2O and benzene-1,4-dicarboxylic acid (H2BDC) or terephthalic acid using N,N-dimethylformamide (DMF) as solvent. The powder was characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and infrared spectroscopy (IR) analysis. The electrochemical properties were investigated in a typical lithium-ion battery electrolyte by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charging and discharging. The synthetized Fe-BDC-DMF metal-organic framework (MOF) contains a mixture of three phases, identified by PXRD as: MOF-235, and MIL-53(Fe) monoclinic with C2/c and P21/c space groups. The structure of the Fe-BDC is built up from Fe3+ ions, terephalates (BDC) bridges and in-situ-generated DMF ligands. The electrochemical measurements conducted in the potential range of 0.5–3.5 V vs. Li+/Li0 show the voltage profiles of Fe-BDC and a plateau capacity of around 175 mAh/g.

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  • 21.
    Ajpi Condori, Cesario
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry. UMSA Univ Mayor San Andres, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz 303, Bolivia..
    Leiva, Naviana
    UMSA Univ Mayor San Andres, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz 303, Bolivia..
    Vargas, Max
    UMSA Univ Mayor San Andres, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz 303, Bolivia..
    Lundblad, Anders
    RISE, Res Inst, Div Safety & Transport Elect, SE-50462 Borås, Sweden..
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Cabrera, Saul
    UMSA Univ Mayor San Andres, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz 303, Bolivia..
    Synthesis and Characterization of LiFePO4-PANI Hybrid Material as Cathode for Lithium-Ion Batteries2020In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 13, no 12, article id 2834Article in journal (Refereed)
    Abstract [en]

    This work focuses on the synthesis of LiFePO4-PANI hybrid materials and studies their electrochemical properties (capacity, cyclability and rate capability) for use in lithium ion batteries. PANI synthesis and optimization was carried out by chemical oxidation (self-assembly process), using ammonium persulfate (APS) and H3PO4, obtaining a material with a high degree of crystallinity. For the synthesis of the LiFePO4-PANI hybrid, a thermal treatment of LiFePO(4)particles was carried out in a furnace with polyaniline (PANI) and lithium acetate (AcOLi)-coated particles, using Ar/H(2)atmosphere. The pristine and synthetized powders were characterized by XRD, SEM, IR and TGA. The electrochemical characterizations were carried out by using CV, EIS and galvanostatic methods, obtaining a capacity of 95 mAhg(-1)for PANI, 120 mAhg(-1)for LiFePO(4)and 145 mAhg(-1)for LiFePO4-PANI, at a charge/discharge rate of 0.1 C. At a charge/discharge rate of 2 C, the capacities were 70 mAhg(-1)for LiFePO(4)and 100 mAhg(-1)for LiFePO4-PANI, showing that the PANI also had a favorable effect on the rate capability.

  • 22.
    Ajpi Condori, Cesario
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry. UMSA Univ Mayor San Andres, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz, Bolivia..
    Leiva, Naviana
    UMSA Univ Mayor San Andres, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz, Bolivia..
    Vargas, Max
    UMSA Univ Mayor San Andres, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz, Bolivia..
    Lundblad, Anders
    Res Inst Sweden, Div Safety & Transport Elect, RISE, SE-50462 Borås, Sweden..
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Cabrera, Saul
    UMSA Univ Mayor San Andres, IIQ Chem Res Inst, Dept Inorgan Chem & Mat Sci Adv Mat, La Paz, Bolivia..
    Synthesis and spectroscopic characterization of NiII coordination network:: Poly-[tris(µ4-Benzene-1,4-dicarboxylato)-tetrakis(µ1-dimethylformamide-κ1O)-trinickel(II)] as material for lithium ion batteries2022In: Journal of Molecular Structure, ISSN 0022-2860, E-ISSN 1872-8014, Vol. 1265, p. 133316-, article id 133316Article in journal (Refereed)
    Abstract [en]

    The compound Ni3(C8H4O4)3(C3H7NO)3, poly-[tris(µ4-Benzene-1,4-dicarboxylato)-tetrakis(µ1-dimethylformamide-κ1O)-trinickel(II)], was synthesized by the solvothermal method prepared via reaction between NiCl2•6H2O and terephthalic acid using N,N-dimethylformamide (DMF) as solvent. The structure was characterized by powder X-ray diffraction and infrared spectroscopy analyses. The electrochemical properties as a potential active material in lithium-ion batteries were characterized by electrochemical impedance spectroscopy and galvanostatic charge-discharge curves in a battery half-cell.

    The characterization results show that the coordination network contains one independent structure in the asymmetric unit. It is constructed from Ni2+ ions, terephthalate bridges and in-situ-generated DMF ligands, forming two similar two-dimensional (2D) layer structures. These similar 2D layers are in an alternating arrangement and are linked with each other by dense H—H interactions (45%) to generate a three-dimensional (3D) supramolecular framework with ordered and disordered DMF molecules.

    The electrochemical measurements, conducted in the potential range of 0.5–3.5 V vs Li/Li+, show that Ni3(C8H4O4)3(C3H7NO)4 has good electrochemical properties and can work as anode in lithium-ion batteries. The material presents an initial specific capacity of ∼420 mAh g−1, which drops during consecutive scans but stabilizes at ∼50 mAh g−1. However, due to the wide potential range there are indications of a gradual collapse of the structure. The electrochemical impedance spectroscopy shows an increase of charge transfer resistance from 24 to 1190 Ohms after cycling likely due to this collapse.

  • 23.
    Akbarkermani, Mohammadreza
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery. Chemical Engineering Department, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey.
    Genceli Güner, Fatma Elif
    Chemical Engineering Department, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey; Polar Research Center (PolReC), Istanbul Technical University, 34469, Maslak, Istanbul, Turkey; Nanotechnology Research and Application Center (ITUNano), Istanbul Technical University, 34469, Istanbul, Turkey.
    Eutectic freeze crystallization in the boric acid–water system2023In: Chemické zvesti, ISSN 0366-6352, E-ISSN 1336-9075, Vol. 77, no 10, p. 5881-5891Article in journal (Refereed)
    Abstract [en]

    Boron compounds are widely used in various industries. Current high rates of boron production/usage generate significant wastes. As an ecologically friendly technology, eutectic freeze crystallization (EFC) has the potential to treat boron wastewater ponds for mineral recovery; however, its feasibility has not been examined before. Here, we determined the eutectic point of boric acid (a major boron compound)-water system to be -0.79 °C and 2.5 ± 0.05 wt%. At the eutectic point, ice and boric acid crystals were isolated from the aqueous solution. The nucleation rate and growth rate of boric acid were considered, as well as the boron content in ice crystals. Our results show that it is feasible to separate boric acid and water from boron waste streams by EFC.

  • 24.
    Al Husseinat, Ali
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Persson, Emma
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Carlhamn Rasmussen, Ran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rynkiewicz, Filip
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Lignin/Carbon Fibre Composites2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The market is in great need of more environmentally friendly alternatives to fossil-based composite materials to obtain a more sustainable future. Lignin is the second most common biopolymer and is a byproduct in the pulping and paper industry. Fractionation of lignin has made it possible to receive lignin with narrow dispersity and low molecular weight, which is suitable for further applications. Modification of lignin structure yields new reactive sites that can be tailored for specific needs. Because of the aromatic structure of lignin, it is a promising renewable resource for production of thermosets. In this project Kraft lignin is sequentially solvent-fractionated and modified in an allylation process with allyl chloride. The allylated lignin is reacted with a cross-linking agent and used to impregnate carbon fibre mats. The resin-coated material is then cured at 125 oC to achieve a composite material. The project also encompasses characterization of the chemical structure of lignin in the different fractions. The morphology and adhesive properties of the lignin as well as the carbon fibres and the composite material was investigated. Although the production of composite material from lignin and carbon fibres were accomplished, bubble formation in the resin was a problem for all composite samples that were prepared, whether it was during solvent evaporation or during curing. By performing the addition of resin to carbon fibre mats in multiple steps, where pressure is added after the first applied layer, it is suggested that complete adhesion to the carbon fibre can be achieved, whilst maintaining adequate resin to carbon fibre ratio. 

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  • 25.
    Alejo Vargas, Lucio Rodrigo
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Analysis of Negative Emission Ammonia Fertilizer (urea) Process2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As the world population keeps increasing, ammonia-based fertilizers like urea are essential to provide food security. However, the current fertilizer industry is based on fossil fuel feedstock (mainly natural gas), making the production process CO2 emission-intensive. More specifically, besides the CO2 emitted during the process, the CO2 captured in urea is also released into the atmosphere after the fertilizer is applied to agricultural soils. Thus, positioning the fertilizer industry among the top four industrial emitters globally. Hence, in order to meet the target of limiting global warming to 1.5 ºC and achieve net-zero emissions by 2050, it is necessary to strengthen the carbon mitigation efforts in the current fertilizer industry. This can be achieved in different ways, such as using renewable biofuels and implementing technologies that can lead to zero/negative CO2 emissions.

    For that reason, the present study presents pathways to achieve a more environmentally friendly fertilizer production process. An overall analysis is performed if negative emissions can be achieved by replacing different fractions of natural gas (used as both feedstock and fuel) with biogas and biomethane and by capturing and storing the CO2 emitted from the process using chemical solvents as activated MDEA and MEA. The results obtained from the study revealed that negative emissions in fertilizer plant can be achieved by retrofitting an existing ammonia plant with a MEA based CO2 capture system (with a carbon capture rate of 90%) for the SMR burner flue gas, and by introducing 50% of biogas in the feedstock (alongside Natural gas), and 75% of biogas in the SMR burner fuel (alongside Natural gas). This initial approach would result in net negative emissions from urea's production and application and require approximately 0.5 kg of biogas per kg of urea produced in this case. Furthermore, the equivalent energy intensity for the negative emission urea plant would be 0.32% and 3.37% lower compared to the fossil fuel-based case without/with CCS, respectively. Ultimately, it is even possible to produce approximately 6% more urea product by replacing a particular fraction of natural gas with biogas. The reason for this increased production is due to the surplus of carbon dioxide by the introduction of biogas. It can be used along with the ammonia product going to storage in the fossil fuel-based case, where there was not enough CO2 to keep the feedstock molar ratio at the urea plant's inlet.

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  • 26.
    Alemrajabi, Mahmood
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Recovery of Rare Earth Elements from an Apatite Concentrate2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Rare earth elements (REE) are a group of 17 elements including lanthanides, yttrium and scandium; which are found in a variety of classes of minerals worldwide. The criticality of the application, lack of high grade and economically feasible REE resources and a monopolistic supply situation has raised significant attention in recovery of these metals from low grade ores and waste materials. In this thesis, the recovery of REE from an apatite concentrate, containing 0.5 mass% of REE, within the nitrophosphate route of fertilizer production has been investigated. Most of the REE (≥ 95%) content can be recovered into a phosphate precipitate with almost 30 mass% REE. Different processes have been developed to convert the REE phosphate precipitate into a more soluble form to obtain a solution suitable for further REE purification and individual separation. It has been shown that after reprecipitation of the REE phosphate concentrate as REE sodium double sulphate and then transformation into a REE hydroxide concentrate, a solution containing 45g/L REE free of Ca, Fe and P can be obtained. The results suggest that the apatite waste after processing of iron ore have the potential to be a very important source for REE in Europe and that the economy is strongly supported by the simultaneous extraction of phosphorous.

    The potential of using hollow fiber supported liquid membrane (HFSLM) extraction in individual and group separation of REE has been investigated. A hollow fiber supported liquid membrane plant in pilot scale has been operated according to the three main configurations: standard hollow fiber supported liquid membrane technology (HFSLM); hollow fiber renewal liquid membrane technology (HFRSLM) and emulsion pertraction technology (EPT). The standard HFSLM operation is more selective than HFRSLM and EPT, while higher metal transport rate is observed in EPT followed by HFRSLM and HFSLM. The HFRLM configuration helps to maintain the performance of the liquid membrane.

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  • 27.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Dephosphorization and impurity removal from a rare earth phosphate concentrate2017Conference paper (Refereed)
  • 28.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Recovery of phosphorous and rare earth elements from an apatite concentrate2018Conference paper (Refereed)
  • 29.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Processing of a rare earth phosphate concentrate obtained in the nitrophosphate process of fertilizer production2019In: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158, Vol. 189, article id 105144Article in journal (Refereed)
    Abstract [en]

    In this study, different processes have been developed and applied to treat a rare earth phosphate concentrate obtained within the nitrophosphate process of fertilizer production. Methods to remove impurities such as Fe and Ca have been investigated as well as to separate the phosphorous and thereby facilitate dissolution of the rare earth elements (REE). These methods include thermal treatment with sodium hydroxide and sodium double sulphate precipitation with and without alkaline conversion, followed by selective dissolution in different acids. The proposed processes were compared and analyzed from the perspective of introducing an appropriate intermediate product for further individual REE separation. The results have shown that after thermal treatment with NaOH at 400 °C, the phosphorous can be removed from the rare earth phosphate concentrate by water leaching. Investigation of different REE phosphate concentrates demonstrated that mixed Ca and REE phases, e.g. REEmCan(PO4)3m+2n/3 and CaHPO4 are less likely to dephosphorize than REE(PO4).nH2O and FePO4.H2O under these conditions. The recovery of REE to a mild acidic solution is limited by the presence of remaining phosphate ions and by the formation of REE oxide phases during the thermal treatment. The results also show that a solution containing 40 g/L REE; free of phosphorous, calcium and iron can be obtained after reprecipitation of the rare earth phosphate concentrate as sodium rare earth double sulphates followed by alkaline conversion with sodium hydroxide and dissolution in nitric acid.

  • 30.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena.
    Rasmuson, Åke C.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena.
    Korkmaz, Kivanc
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Recovery of rare earth elements from nitrophosphoric acid solutions2017In: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158, Vol. 169, p. 253-262Article in journal (Refereed)
    Abstract [en]

    In the present study, the recovery of rare earth elements (REEs) from an apatite concentrate in the nitrophosphate process of fertilizer production has been studied. The apatite concentrate has been recovered from iron ore tailings in Sweden by flotation. In the first step, the apatite is digested in concentrated nitric acid, after which Ca(NO3)2.4H2O is separated by cooling crystallization. The solution is then neutralized using ammonia whereby the REEs precipitate mainly as phosphates (REEPO4.nH2O) and together with calcium as REEn Cam (PO4)(3n + 2m) / 3. In this work, the degree of rare earth coprecipitation during seeded cooling crystallization of Ca(NO3)2.4H2O has been studied. The solubility of calcium nitrate tetrahydrate (Ca(NO3)2.4H2O) in acidic nitrophosphoric acid solutions in the temperature range of − 2 °C to 20 °C has been determined. For the neutralization step, it is shown that the calcium concentration and the final pH play an important role in determining the concentration of REEs in the precipitate. It is found that reaching maximum recovery of REE with minimum simultaneous precipitation of calcium requires careful control of the final pH to about 1.8. It is further observed that the precipitation yield of REEs and iron is favored by a longer residence time and higher temperature. Finally, the effect of seeding with synthesized REE phosphate crystals as well as a mixture of REE and Ca phosphates on the precipitation rate and the composition of the precipitate was studied.

  • 31.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Upgrading of a rare earth phosphate concentrate within the nitrophosphate process2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 198, p. 551-563Article in journal (Refereed)
    Abstract [en]

    In the nitrophosphate process of fertilizer production, rare earth elements (REE) can be recovered as a REE phosphate concentrate. In this process, after digestion of apatite in concentrated nitric acid, Ca(NO3)2.4H2O is first separated by cooling crystallization and then the REE are precipitated in phosphate form by a partial neutralization step using ammonia. The obtained REE phosphate concentrate is contaminated by mainly calcium and iron, and the main solid phases are CaHPO4.2H2O, FePO4.2H2O and REEPO4.nH2O.

    In this study, a process to obtain a concentrate more enriched with REE with low concentration of calcium and iron and free of phosphorous is developed. In the developed process, enrichment and dephosphorization of the rare earth phosphate concentrate has been achieved by selective dissolution and re-precipitation of the REE as a sodium REE double sulfate salt. It is shown that by selective dissolution of the REE concentrate in nitric acid at a pH of 2.4, most of the calcium and phosphorus are dissolved, and a solid phase more enriched in REE is obtained. Thereafter, the REE phosphate concentrate is first dissolved in a mixture of sulfuric-phosphoric acid and then the REE are reprecipitated as NaREE(SO4)2.H2O by addition of a sodium salt. More than 95% of the Ca, Fe and P are removed and a REE concentrate containing almost 30 mass% total REE is obtained.

  • 32.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Ricknell, Jonas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Samak, Sakarias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rodriguez Varela, Raquel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Martinez, Joaquin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Hedman, Fredrik
    IVL Swedish Environmental Research Institute.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Separation of Rare-Earth Elements Using Supported Liquid Membrane Extraction in Pilot Scale2022In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045Article in journal (Refereed)
    Abstract [en]

    The use of supported liquid membrane extraction for recovery and separation of rare-earth elements (REEs) has been investigated. Experiments have been carried out using the different configurations: (1) standard hollow fiber supported liquid membrane operation (HFSLM), (2) renewal liquid membrane operation (HFRLM), and (3) emulsion pertraction technology (EPT). The experiments were performed in pilot scale using a hollow fiber module with a mass transfer surface area of 8 m2. Synthetic feed solution was used with compositions based on a process for recovery of REE from an apatite concentrate. The total concentration of REE in the feed was varied from 1 to 22 mM REE and the pH was varied in the range 1.5–3.2. Di(2-ethylhexyl) phosphoric acid (D2HEPA) diluted in kerosene, 10% (v/v), was used as the organic membrane solution, and 3 M HCl was used as stripping solution. In supported liquid membrane extraction, the extraction performance is governed by both the kinetics of REE transport through the membrane and by thermodynamics. The effect of feed composition on the selectivity and transport of REE through the liquid membrane have been investigated. The results show that the liquid membrane is more selective toward the heavy REE at lower pH values and higher REE concentration. HFRLM shows a higher transport rate than HFSLM, while the HFSLM configuration gives a higher selectivity toward individual REE. The membrane performance in HFSLM configuration rapidly decays with time, while in the HFRLM and EPT configurations, the performance is much more stable. Possible mechanisms for decaying membrane performance are discussed, and gel formation is identified as being of significant importance. Gel formation is observed at an organic loading above ∼46% for Nd, 38% for Y, 46% for Dy, and 65% for Er. The work performed in this study serves as an initial step to demonstrate that HFRLM and EPT can provide stable operation and be feasible options for processing of REE liquors. A process flow diagram for the recovery of the REE, present in the apatite concentrate, in three fractions is proposed based on the results from this study.

  • 33.
    Alemrajabi, Mahmoud
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Recovery of REE from an apatite concentrate in the nitrophosphate process of fertilizer production.2015Conference paper (Refereed)
  • 34.
    Altantzis, Ikaros
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Enhancing Mineral Carbonation of Olivine with CO22023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Carbon dioxide (CO2) emissions from the energy production industry and the transportation sector globally negatively affect the environment. A prominent example is the interconnection of carbon with the greenhouse effect. Countries have agreed to mitigate their emissions and try to fulfill the target of 1.5 oC average temperature increase by 2030, but in order to do so the global emissions of CO2 from fossil fuels and industrial processes will still lead up to the astonishing amount of 40 Gtons of CO2 each year until 2100. 

    It is apparent that processes that try to take advantage of the emitted CO2 creating valuable products with negative emissions are highly desired. One of these is mineral carbonation, where CO2 and minerals dissolve in an alkaline solution and form stable products. Many factors affect the rate at which mineral carbonation happens. The effect of the particle size of the mineral in the process will be investigated, along the CO2 dissolution rate through the overall gas-liquid mass transfer coefficient (kLa), in order to get a better understanding of the process.

    Experiments were conducted with a batch reactor provided by Paebbl AB and a mathematical model was developed in Matlab. The experimental and numerical results, in regards to the particle size, were then compared for the cases of three resistances. This model can be developed further for use in a continuous mineralization process. The results revealed that increasing the particle size of olivine leads to a significant increase in the time required for total conversion, irrespective of the resistance type. The modelled resistances were found to inadequately describe the process, suggesting a simultaneous and uniform effect of all three resistances on olivine mineralization, in addition to the effect of other possible limitations such as impurities and by-products. Mineralization experiments with 20μm particles and a duration of 1 hour led to 34.4% conversion, whereas experiments with 10μm particles and a duration of 2 hours resulted in 46.7% conversion. Finally, the initial investigation of the mass transfer limitations in a system of CO2 and water led to an average kLa coefficient of 191 h-1, suggesting that the CO2 dissolution rate is not the limiting factor. However, the impact of lower stirring rates remains unexplored due to the absence of appropriate instrumentation and the behaviour of the (CO2 + olivine) system should also be studied. Future research should aim to address these limitations.

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  • 35.
    Alterby, Malin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Johnson, Emily
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Jonason, Anton
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Svensson, Denize
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    3D Printing Hydrogel Artificial Muscles and Microrobotics2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this lab was to investigate the printability of cellulose nanofiber/carbon nanotubes, their functions as actuators, and to compare these properties with MXene/nano cellulose gels. Data on MXene/nano cellulose gel was obtained from previous research made by Hamedi labs. Data on carbon nanotubes were collected through experiments evaluating different concentrations and sonication times to yield a gel with high conductivity and viscosity. While it was concluded that both gels could be printed into 2D or 3D shapes, the latter failed to maintain its structure over time due to issues with drying. However, it was found that only 2D MXene/CNF could be used as a reversible actuator.

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  • 36.
    Amara, Soumia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    CO2 capture in industry using chilled ammonia process2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    CO2 capture and storage (CCS) is estimated to reduce 14% of the global CO2 emissions in the 2 °C scenario presented by the International Energy Agency. Moreover, post combustion capture is identified as a potential method for CO2 capture from industry since it can be easily retrofitted without disturbing the core industrial process. Among the post-combustion capture methods, absorption using mono-ethanol amine (MEA) is the most mature technology that has been demonstrated at plant scale. However, using chilled ammonia process as a post combustion capture technology in a cement industry can reduce 47% energy penalty for CO2 capture when compared to the conventional MEA absorption method. 

    Hence, the current project aims at analyzing the chilled ammonia process when integrated with steel and ammonia plants. Key performance indicator like specific primary energy consumption per kilogram of CO2 avoided (SPECCA) is estimated and compared with MEA absorption method. Firstly, chilled ammonia process (CAP) for cement plant was used as reference case. Then, CAP for steel and ammonia processes was optimized by the means of the decision variables affecting the capture and energy efficiency. The energy consumption per kg CO2 captured and SPECCA was lower for the higher CO2 concentration in the flue gas. Results for SPECCA were 3,56, 3,52 and 3,61 MJ/kg CO2 for cement, steel, and ammonia plants, respectively. 

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  • 37. An, A. K.
    et al.
    Tyagi, V. K.
    Kumar, M.
    Cetecioglu, Zeynep
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Clean Energy and Resource Recovery: Wastewater Treatment Plants as Biorefineries, Volume 22021Book (Other academic)
    Abstract [en]

    Clean Energy and Resource Recovery: Wastewater Treatment Plants as Bio-refineries, Volume 2, summarizes the fundamentals of various treatment modes applied to the recovery of energy and value-added products from wastewater treatment plants. The book addresses the production of biofuel, heat, and electricity, chemicals, feed, and other products from municipal wastewater, industrial wastewater, and sludge. It intends to provide the readers an account of up-to-date information on the recovery of biofuels and other value-added products using conventional and advanced technological developments. The book starts with identifying the key problems of the sectors and then provides solutions to them with step-by-step guidance on the implementation of processes and procedures. Titles compiled in this book further explore related issues like the safe disposal of leftovers, from a local to global scale. Finally, the book sheds light on how wastewater treatment facilities reduce stress on energy systems, decrease air and water pollution, build resiliency, and drive local economic activity. As a compliment to Volume 1: Biomass Waste Based Biorefineries, Clean Energy and Resource Recovery, Volume 2: Wastewater Treatment Plants as Bio-refineries is a comprehensive reference on all aspects of energy and resource recovery from wastewater. The book is going to be a handy reference tool for energy researchers, environmental scientists, and civil, chemical, and municipal engineers interested in waste-to-energy.

  • 38.
    Andersson, Filippa
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Integrating biomass gasification with electric arc furnace steel making2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Greenhouse gas emissions are increasing worldwide, and new techniques are being adopted to suppress the emissions. The steel sector is responsible for 7% of the emissions. 25% ofthe world’s steel production is made through the recycling technique EAF. Throughout the recycling process, 500 kg CO2 gets emitted per ton of liquid steel produced. An opportunity to lower these direct emissions is to couple the EAF process to biomass gasification and CO2 utilisation process. The proposed solution in this thesis is to utilise the off-gases in the gasification process and create high-valuable products. The project evaluates the technical feasibility via energy efficiency and carbon utilisation. The proposed process was simulated using Aspen Plus.

    A problem with the off-gases from EAF gasification is the fluctuation in composition. Three cases of off-gas composition were therefore investigated. Case 1 was the average off-gas composition, while cases 2 and 3 were extreme with high CO and CO2 content, respectively. The result showed that the syngas composition strongly depends on the gasifying agent. In all cases, the energy efficiency increased, and the direct emissions decreased. Case 1 generally showed the highest efficiency and carbon utilisation, while the CO2 heavily case (case 3) had the lowest. A continuous flow of gasifying agents is required to run the gasification process. Since EAF is a batch process, air gasification runs when off-gases are unavailable. The desired outcome of air gasification is to produce syngas similar to off-gas gasification. The results showed that air infiltration in off-gases is favourable for more similar syngas composition.

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  • 39.
    Andersson, Filippa
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Bengtsson, Sofia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Lagergren, Jonas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Vikström, Madeleine
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Absorption av koldioxid i ammoniaklösning2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Gasformig koldioxid kan absorberas i en ammoniaklösning och bilda salt. De möjliga produkterna är ammoniumvätekarbonat (NH4HCO3), ammoniumkarbamat (NH2COONH4) och ammoniumkarbonat ((NH4)2CO3). Ammoniak är gasformigt i rumstemperatur. För att förhindra avdunstning av ammoniak undersöktes det i den här rapporten om nedkylning av reaktionslösningen eller ett oljelager ovanför skulle kunna förhindra detta och därmed tillåta saltbildning i lösningen. Dessutom skulle absorptionen genomföras utan både oljelager och nedkylt förhållande för att bestämma vad som var mest effektivt för att ge ett så högt utbyte som möjligt. För bestämning av de bildade salternas sammansättning användes XRD som analysmetod. 

    Resultatet från experimentet visade att salterna bildades i gasfasen och inget salt erhölls från vätskefasen. Orsaken till det är inte fastslagen, men tros bero på parametrar som salternas löslighet, lösningens pH, flödeshastighet på koldioxiden som gynnar ammoniakens avdunstning samt temperaturen. Utbytet från de olika försöksuppställningarna blev lågt i samtliga experiment, som högst erhölls relativt utbyte på 1,5%. Experimentet som gav högst relativt utbyte var försök vid 15% ammoniakkoncentration och koldioxidflöde på 181 ml CO2/min. Vid detta försök gjordes inga åtgärder för att förhindra ammoniakavdunstning från lösningen. Av de proverna som analyserades med XRD erhölls endast den önskade produkten med säkerhet i ett av proverna (isbad, 15 % NH3, 181 ml CO2/min). För att bestämma optimala reaktionsbetingelser krävs vidare studier.

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  • 40.
    Andersson, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Application of Liquid Hydrogen Carriers in Hydrogen Steelmaking2021In: Energies, E-ISSN 1996-1073, Vol. 14, no 5, p. 1392-Article in journal (Refereed)
    Abstract [en]

    Steelmaking is responsible for approximately one third of total industrial carbon dioxide (CO2) emissions. Hydrogen (H2) direct reduction (H-DR) may be a feasible route towards the decarbonization of primary steelmaking if H2 is produced via electrolysis using fossil-free electricity. However, electrolysis is an electricity-intensive process. Therefore, it is preferable that H2 is predominantly produced during times of low electricity prices, which is enabled by the storage of H2. This work compares the integration of H2 storage in four liquid carriers, methanol (MeOH), formic acid (FA), ammonia (NH3) and perhydro-dibenzyltoluene (H18-DBT), in H-DR processes. In contrast to conventional H2 storage methods, these carriers allow for H2 storage in liquid form at moderate overpressures, reducing the storage capacity cost. The main downside to liquid H2 carriers is that thermochemical processes are necessary for both the storage and release processes, often with significant investment and operational costs. The carriers are compared using thermodynamic and economic data to estimate operational and capital costs in the H-DR context considering process integration options. It is concluded that the use of MeOH is promising compared to the other considered carriers. For large storage volumes, MeOH-based H2 storage may also be an attractive option to the underground storage of compressed H2. The other considered liquid H2 carriers suffer from large thermodynamic barriers for hydrogenation (FA) or dehydrogenation (NH3, H18-DBT) and higher investment costs. However, for the use of MeOH in an H-DR process to be practically feasible, questions regarding process flexibility and the optimal sourcing of CO2 and heat must be answered

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  • 41.
    Andersson, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Improving the economics of fossil-free steelmaking via co-production of methanolManuscript (preprint) (Other academic)
    Abstract [en]

    Steelmaking is responsible for 7% of the global net emissions of carbon dioxide and heavily reducing emissions from currently dominating steelmaking processes is difficult and costly. Recently, new steelmaking processes based on the reduction of iron ore with hydrogen (H2) produced via water electrolysis have been suggested. If the electricity input to such processes is fossil-free, near-zero carbon dioxide emissions steelmaking is achievable. However, the high electricity demand of electrolysis is a significant implementation barrier. A H2 storage may alleviate this via allowing a larger share of H2 to be produced at low electricity prices. However, accurately forecasting the dynamics of electricity markets is challenging. This increases the risk of investment in a H2 storage. Here we evaluate a novel methanol-based H2 storage concept for a H2-based steelmaking process that also allows for the co-production of methanol. During electricity price peaks, the methanol can be reformed to produce H2 for the steelmaking process. During prolonged periods of low electricity prices, excess methanol can be produced and sold off, thus improving the prospects of storage profitability. We use historical electricity prices and a process model to evaluate methanol-fossil-free steel co-production schemes. Methanol co-production has the potential to improve the economics of H2 supply to a fossil-free steelmaking process by up to an average of 0.40 €/kg H2 across considered scenarios, equivalent to a reduction in H2 production electricity costs of 25.0%.

  • 42.
    Andersson, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Non-geological hydrogen storage for fossil-free steelmaking2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the last half-century, global steel use has increased more than threefold and further growth is expected, particularly in developing economies. However, steelmaking is currently responsible for 7% of the global net carbon dioxide (CO2) emissions, and any substantial further optimization of existing processes that utilize fossil fuels for iron ore reduction is infeasible. Therefore, steelmaking must change for climate change mitigation targets to be achievable. Hydrogen (H2) steelmaking using H2 produced via electrolysis is one way forward. A challenge is the substantial electricity demand of electrolysis. H2 storage may lower the electricity cost of electrolysis by allowing a larger share of H2 to be produced when the electricity price is low. Existing experience with large-scale H2 storage is limited to salt caverns and the construction of such caverns requires suitable geological formations, which are neither ubiquitous nor well-distributed. However, geologically-independent H2 storage technologies have not previously been evaluated for integration with H2 steelmaking. This is the aim of this thesis. H2 storage technologies were reviewed and liquid H2 carriers were identified as the most techno-economically feasible non-geological options. Out of these liquid carriers, methanol (CH3OH) was found particularly promising for H2 steelmaking due to the low heat demand of its dehydrogenation, its low-cost storage, and the high technological readiness of plants for both its production and dehydrogenation. A complete CH3OH-based H2 storage concept was developed, including processes for CO2 and heat supply. Its ability to reduce the H2 production cost in a H2 steelmaking process was evaluated via a deterministic optimization method based on historical electricity prices. Results indicate that CH3OH-based storage may be competitive with geological storage options, especially for cases with long-duration electricity price patterns.  The option to also sell off accumulated CH3OH from the storage was investigated. Such steel and CH3OH co-production may improve storage utilization and reduce the risk of investment into H2 storage as it allows for profitability to be reached under a more diverse set of electricity market conditions.

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  • 43.
    Andersson, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Grönkvist, Stefan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    A comparison of two hydrogen storages in a fossil-free direct reduced iron process2021In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 46, no 56, p. 28657-28674Article in journal (Refereed)
    Abstract [en]

    Hydrogen direct reduction has been proposed as a means to decarbonize primary steelmaking. Preferably, the hydrogen necessary for this process is produced via water electrolysis. A downside to electrolysis is the large electricity demand. The electricity cost of water electrolysis may be reduced by using a hydrogen storage to exploit variations in electricity price, i.e., producing more hydrogen when the electricity price is low and vice versa. In this paper we compare two kinds of hydrogen storages in the context of a hydrogen direct reduction process via simulations based on historic Swedish electricity prices: the storage of gaseous hydrogen in an underground lined rock cavern and the storage of hydrogen chemically bound in methanol. We find the methanol-based storages to be economically advantageous to lined rock caverns in several scenarios. The main advantages of methanol-based storage are the low investment cost of storage capacity and the possibility to decouple storage capacity from rate capacity. Nevertheless, no storage option is found to be profitable for historic Swedish electricity prices. For the storages to be profitable, electricity prices must be volatile with relatively frequent high peaks, which has happened rarely in Sweden in recent years. However, such scenarios may become more common with the expected increase of intermittent renewable power in the Swedish electricity system.

  • 44.
    Andersson, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Grönkvist, Stefan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Improving the economics of fossil-free steelmaking via co-production of methanol2022In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 350, p. 131469-, article id 131469Article in journal (Refereed)
    Abstract [en]

    Steelmaking is responsible for 7% of the global net emissions of carbon dioxide and heavily reducing emissions from currently dominating steelmaking processes is difficult and costly. Recently, new steelmaking processes based on the reduction of iron ore with hydrogen (H-2) produced via water electrolysis have been suggested. If the electricity input to such processes is fossil-free, near-zero carbon dioxide emissions steelmaking is achievable. However, the high electricity demand of electrolysis is a significant implementation barrier. A H-2 storage may alleviate this via allowing a larger share of H-2 to be produced at low electricity prices. However, accurately forecasting electricity market dynamics is challenging. This increases the risk of investment in a H-2 storage. Here we evaluate a novel methanol-based H-2 storage concept for H-2-based steelmaking that also allows for the coproduction of methanol. During electricity price peaks, the methanol can be reformed to produce H-2 for the steelmaking process. During prolonged periods of low electricity prices, excess methanol can be produced and sold off, thus improving the prospects of storage profitability. We use historical electricity prices and a process model to evaluate methanol and fossil-free steel co-production schemes. Methanol co-production is found to have the potential to improve the economics of H-2 supply to a fossil-free steelmaking process by up to an average of 0.40 (sic)/kg H-2 across considered scenarios, equivalent to a 25.0% reduction in H-2 production electricity costs.

  • 45.
    Andersson, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Grönkvist, Stefan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Large-scale storage of hydrogen2019In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 44, no 23, p. 11901-11919Article in journal (Refereed)
    Abstract [en]

    The large-scale storage of hydrogen plays a fundamental role in a potential future hydrogen economy. Although the storage of gaseous hydrogen in salt caverns already is used on a full industrial scale, the approach is not applicable in all regions due to varying geological conditions. Therefore, other storage methods are necessary. In this article, options for the large-scale storage of hydrogen are reviewed and compared based on fundamental thermodynamic and engineering aspects. The application of certain storage technologies, such as liquid hydrogen, methanol, ammonia, and dibenzyltoluene, is found to be advantageous in terms of storage density, cost of storage, and safety. The variable costs for these high-density storage technologies are largely associated with a high electricity demand for the storage process or with a high heat demand for the hydrogen release process. If hydrogen is produced via electrolysis and stored during times of low electricity prices in an industrial setting, these variable costs may be tolerable.

  • 46.
    Andersson, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Krüger, Andries
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Grönkvist, Stefan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Methanol as a carrier of hydrogen and carbon in fossil-free production of direct reduced iron2020In: Energy Conversion and Management: X, ISSN 2590-1745, Vol. 7, no 100051Article in journal (Refereed)
    Abstract [en]

    Steelmaking is responsible for around 7% of the global emissions of carbon dioxide and new steelmaking processes are necessary to reach international climate targets. As a response to this, steelmaking processes based on the direct reduction of iron ore by hydrogen produced via water electrolysis powered by renewable electricity have been suggested. Here we present a novel variant of hydrogen-based steelmaking incorporating methanol as a hydrogen and carbon carrier together with high-temperature co-electrolysis of water and carbon dioxide and biomass oxy-fuel combustion. The energy and mass balances of the process are analyzed. It is found that this methanol-based direct reduction process may potentially offer a number of process-related advantages over a process based on pure hydrogen, featuring several process integration options. Notably, the electricity and total energy use of the steelmaking process could be reduced by up to 25% and 8% compared to a reference pure-hydrogen process, respectively. The amount of high-temperature (>200 °C) heat that must be supplied to the process could also be reduced by up to approximately 34%, although the demand for medium-temperature heat is substantially increased. Furthermore, the suggested process could allow for the production of high-quality direct reduced iron with appropriate carburization to alleviate downstream processing in an electric arc furnace, which is not the case for a process based on pure hydrogen.

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  • 47.
    Andersson, Malin
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Decision and Control Systems (Automatic Control). Scania CV AB, Granparksvagen 10, S-15148 Södertälje, Sweden..
    Streb, Moritz
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Ko, Jing Ying
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Klass, Verena Lofqvist
    Scania CV AB, Granparksvagen 10, S-15148 Södertälje, Sweden..
    Klett, Matilda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry. Scania CV AB, Granparksvagen 10, S-15148 Södertälje, Sweden..
    Ekström, Henrik
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry. COMSOL AB, Tegnergatan 23, S-11140 Stockholm, Sweden..
    Johansson, Mikael
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Decision and Control Systems (Automatic Control).
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    p Parametrization of physics-based battery models from input-output data: A review of methodology and current research2022In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 521, p. 230859-, article id 230859Article, review/survey (Refereed)
    Abstract [en]

    Physics-based battery models are important tools in battery research, development, and control. To obtain useful information from the models, accurate parametrization is essential. A complex model structure and many unknown and hard-to-measure parameters make parametrization challenging. Furthermore, numerous applications require non-invasive parametrization relying on parameter estimation from measurements of current and voltage. Parametrization of physics-based battery models from input-output data is a growing research area with many recent publications. This paper aims to bridge the gap between researchers from different fields that work with battery model parametrization, since successful parametrization requires both knowledge of the underlying physical system as well as understanding of theory and concepts behind parameter estimation. The review encompasses sensitivity analyses, methods for parameter optimization, structural and practical identifiability analyses, design of experiments and methods for validation as well as the use of machine learning in parametrization. We highlight that not all model parameters can accurately be identified nor are all relevant for model performance. Nonetheless, no consensus on parameter importance could be shown. Local methods are commonly chosen because of their computational advantages. However, we find that the implications of local methods for analysis of non-linear models are often not sufficiently considered in reviewed literature.

  • 48.
    Andersson, Malin
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Decision and Control Systems (Automatic Control).
    Streb, Moritz
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Prathimala, Venu Gopal
    Siddiqui, Aamer
    Lodge, Andrew
    Löfqvist Klass, Verena
    Klett, Matilda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Johansson, Mikael
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Decision and Control Systems (Automatic Control).
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Electrochemical model-based aging-adaptive fast charging of automotive lithium-ion cellsManuscript (preprint) (Other academic)
    Abstract [en]

    Fast charging of electric vehicles remains a compromise between charging time and degradation penalty. Conventional battery management systems use experience-based charging protocols that are expected to meet vehicle lifetime goals. Novel electrochemical model-based battery fast charging uses a model to observe internal battery states. This enables control of charging rates based on states such as the lithium-plating potential but relies on an accurate model as well as accurate model parameters. However, the impact of battery degradation on the model’s accuracy and therefore the fitness of the estimated optimal charging procedure is often not considered. In this work, we therefore investigate electrochemical model-based aging-adaptive fast charging of automotive lithium-ion cells. First, an electrochemical model is identified at the beginning of life for 6 automotive prototype cells and the electrochemically constrained fast-charge is designed. The model parameters are then periodically re-evaluated during a cycling study and the charging procedure is updated to account for cell degradation. The proposed method is compared with two reference protocols to investigate both the effectiveness of selected electrochemical constraints as well as the benefit of aging-adaptive usage. Finally, post-mortem characterization is presented to highlight the benefit of aging-adaptive battery utilization.

  • 49.
    Anil, Athira
    et al.
    Department of Material Science and Engineering, Ångström Laboratory, Uppsala University, Box 35 751 03 Uppsala Sweden.
    White, Jai
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Campos dos Santos, Egon
    Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai 980-8577 Japan.
    Terekhina, Irina
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm 106 Sweden.
    Johnsson, Mats
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm 106 Sweden.
    Pettersson, Lars G.M.
    Department of Physics, Stockholm University, Stockholm 106 Sweden.
    Cornell, Ann M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Salazar-Alvarez, German
    Department of Material Science and Engineering, Ångström Laboratory, Uppsala University, Box 35 751 03 Uppsala Sweden.
    Effect of pore mesostructure on the electrooxidation of glycerol on Pt mesoporous catalysts2023In: Journal of Materials Chemistry A, ISSN 2050-7488, E-ISSN 2050-7496, Vol. 11, no 31, p. 16570-16577Article in journal (Refereed)
    Abstract [en]

    Glycerol is a renewable chemical that has become widely available and inexpensive owing to the increased production of biodiesel. Noble metal materials are effective catalysts for the production of hydrogen and value-added products through the electrooxidation of glycerol. In this study, we developed three platinum systems with distinct pore mesostructures, e.g., hierarchical pores (HP), cubic pores (CP) and linear pores (LP), all with high electrochemically active surface area (ECSA). The ECSA-normalized GEOR catalytic activity of the systems follows HPC > LPC > CPC > commercial Pt/C. Regarding the oxidation products, we observe glyceric acid as the main three-carbon product (C3), with oxalic acids as the main two-carbon oxidation product. DFT-based theoretical calculations support the glyceraldehyde route going through tartronic acid towards oxalic acid and also help in understanding why the dihydroxyacetone (DHA) route is active despite the absence of DHA amongst the observed oxidation products.

  • 50.
    Ansarian, Zahra
    et al.
    Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, 51666-16471 Tabriz, Iran; Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA.
    Khataee, Alireza
    Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, 51666-16471 Tabriz, Iran; Department of Environmental Engineering, Gebze Technical University, 41400 Gebze, Turkey.
    Orooji, Yasin
    College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China.
    khataee, Amirreza
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Arefi-Oskoui, Samira
    Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, 51666-16471 Tabriz, Iran; Department of Chemical Industry, Technical and Vocational University (TVU), Tehran, Iran.
    Ghasali, Ehsan
    College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China.
    Titanium germanium carbide MAX phase electrocatalysts for supercapacitors and alkaline water electrolysis processes2023In: Materials Today Chemistry, E-ISSN 2468-5194, Vol. 33, article id 101714Article in journal (Refereed)
    Abstract [en]

    Developing electrochemically active, stable, and low-cost electrocatalysts for electrochemical devices is a significant breakthrough. Accordingly, MAX phases, emerging three-dimensional materials, are considered outstanding candidates due to their excellent electrocatalytic and electrochemical properties. Herein, the titanium germanium carbide (Ti3GeC2) MAX phase with a layered structure manufactured through reactive sintering was regarded as the electrocatalyst. In the current work, the electrocatalytic activity of the Ti3GeC2 was investigated for electrochemical devices. It was observed that adding activated carbon to the Ti3GeC2 enhances the conductivity and active area, leading to an excellent specific capacitance (349 Fg-1) for supercapacitors. Also, the capacitance of Ti3GeC2 was increased by increasing the number of cyclic voltammetry cycles. In another application, Ti3GeC2 showed substantial activity for hydrogen and oxygen evolution reactions in alkaline media. As a result, the alkaline water electrolysis system using Ti3GeC2 showed the highest current density of 10 mA cm−2 at 1.36 V and outstanding stability over 400 cycles.

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