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  • 1.
    Abdel-Magied, Ahmed F.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Nasser Abdelhamid, Hani
    Ashour, Radwa M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Zou, Xiaodong
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Hierarchical porous zeolitic imidazolate framework nanoparticles for efficient adsorption of rare-earth elements2019Ingår i: Microporous and Mesoporous Materials, ISSN 1387-1811, E-ISSN 1873-3093, Vol. 278, s. 175-184Artikel i tidskrift (Refereegranskat)
    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.

  • 2.
    Alemrajabi, Mahmood
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Korkmaz, Kivanc
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Dephosphorization and impurity removal from a rare earth phosphate concentrate2017Konferensbidrag (Refereegranskat)
  • 3.
    Alemrajabi, Mahmood
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Korkmaz, Kivanc
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Rasmuson, Åke C.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Isolation of rare earth element phosphate precipitate in the nitrophosphate process for manufacturing of fertilizer2016Ingår i: IMPC 2016 - 28th International Mineral Processing Congress, Canadian Institute of Mining, Metallurgy and Petroleum , 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the present study, the recovery of rare earth elements (REE) in the nitrophosphate process of fertilizer production is investigated. The apatite has been recovered from iron ore tailings by flotation. After digestion of apatite in concentrated nitric acid, Ca(NO3)2.4H2O is first separated by cooling crystallization and then the REEs are recovered by precipitation. Optimum conditions in these steps have been determined in a previous study. The precipitate mainly consists of CaHPO4.2H2O and REE phosphates. In the present study, selective dissolution and re-precipitation have been studied in order to obtain a precipitate that is more concentrated in REEs. The precipitate was selectively dissolved in nitric and phosphoric acid at different acidities (pH 6 to 0) with the liquid /solid ratio of 100 mL/g. It is shown that most of the CaHPO4.2H2O and other calcium containing compounds will be dissolved at pH 2 while the REE phosphates are not dissolved above a pH of approximately 2. Thus, by partial dissolution of the REE precipitate at pH 2.5 most of the solid calcium phosphates will be dissolved and the remaining solid phase, which is more concentrated in REEs, can be filtered off as a fairly concentrated REE solid mass and the liquor can be recycled back to recover more P nutrients. Alternatively, the REE enriched precipitate was dissolved completely in nitric acid and re-precipitated again by addition of ammonium hydroxide to pH 1.2. A chemical equilibrium software, MEDUSA (Puigdomenech, 2013) has been used to evaluate the experimental results and to estimate the optimum conditions for selectively dissolving the precipitate. 

  • 4.
    Alemrajabi, Mahmood
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Rasmuson, Åke
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Recovery of phosphorous and rare earth elements from an apatite concentrate2018Konferensbidrag (Refereegranskat)
  • 5.
    Alemrajabi, Mahmood
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Korkmaz, Kivanc
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Processing of a rare earth phosphate concentrate obtained in the nitrophosphate process of fertilizer production2019Ingår i: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158, Vol. 189, artikel-id 105144Artikel i tidskrift (Refereegranskat)
    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.

  • 6.
    Alemrajabi, Mahmood
    et al.
    KTH.
    Rasmuson, Åke C.
    KTH.
    Korkmaz, Kivanc
    Forsberg, Kerstin
    KTH.
    Processing of a rare earth phosphate concentrate obtained inthe nitrophosphate process of fertilizer productionManuskript (preprint) (Övrigt vetenskapligt)
  • 7.
    Alemrajabi, Mahmood
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Rasmuson, Åke C.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Korkmaz, Kivanc
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Recovery of rare earth elements from nitrophosphoric acid solutions2017Ingår i: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158, Vol. 169, s. 253-262Artikel i tidskrift (Refereegranskat)
    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.

  • 8.
    Alemrajabi, Mahmood
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Korkmaz, Kivanc
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Upgrading of a rare earth phosphate concentrate within the nitrophosphate process2018Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 198, s. 551-563Artikel i tidskrift (Refereegranskat)
    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.

  • 9.
    Alemrajabi, Mahmoud
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Recovery of REE from an apatite concentrate in the nitrophosphate process of fertilizer production.2015Konferensbidrag (Refereegranskat)
  • 10.
    Ashour, Radwa M.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Abdel-Magied, Ahmed F.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Wu, Qiong
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Olsson, Richard T.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Polymera material.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Green Synthesis of Metal-Organic Framework Bacterial Cellulose Nanocomposites for Separation Applications2020Ingår i: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 12, nr 5Artikel i tidskrift (Refereegranskat)
  • 11.
    Ashour, Radwa M.
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Funktionella material, FNM. Nuclear Materials Authority, Egypt.
    El-sayed, R.
    Abdel-Magied, A. F.
    Abdel-khalek, A. A.
    Ali, M. M.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Uheida, Abdusalam
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Funktionella material, FNM.
    Muhammed, Mamoun
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Funktionella material, FNM.
    Dutta, Joydeep
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Funktionella material, FNM.
    Selective separation of rare earth ions from aqueous solution using functionalized magnetite nanoparticles: kinetic and thermodynamic studies2017Ingår i: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 327, s. 286-296Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Separation of rare earth ions (RE3+) from aqueous solution is a tricky problem due to their physico-chemical similarities of properties. In this study, we investigate the influence of the functionalized ligands on the adsorption efficiency and selective adsorption of La3+, Nd3+, Gd3+ and Y3+ from aqueous solution using Magnetite (Fe3O4) nanoparticles (NPs) functionalized with citric acid (CA@Fe3O4 NPs) or L-cysteine (Cys@Fe3O4 NPs). The microstructure, thermal behavior and surface functionalization of the synthesized nanoparticles were studied. The general adsorption capacity of Cys@Fe3O4 NPs was found to be high (98 mg g−1) in comparison to CA@Fe3O4 NPs (52 mg g−1) at neutral pH 7.0. The adsorption kinetic studies revealed that the adsorption of RE3+ ions follows a pseudo second-order model and the adsorption equilibrium data fits well to the Langmuir isotherm. Thermodynamic studies imply that the adsorption process was endothermic and spontaneous in nature. Controlled desorption within 30 min of the adsorbed RE3+ ions from both Cys@Fe3O4 NPs and CA@Fe3O4 NPs was achieved with 0.5 M HNO3. Furthermore, Cys@Fe3O4 NPs exhibited a higher separation factor (SF) in the separation of Gd3+/La3+, Gd3+/Nd3+, Gd3+/Y3+ ions compared to CA@Fe3O4 NPs.

  • 12.
    Ashour, Radwa
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik. Nuclear Materials Authority, P.O. Box 530, 11381 El Maadi, Cairo, Egypt.
    Samouhos, Michail
    Swedish University of Agricultural Sciences, Department of Molecular Sciences, Uppsala BioCentre.
    Polido Legaria, Elizabeth
    Swedish University of Agricultural Sciences, Department of Molecular Sciences, Uppsala BioCentre.
    Svärd, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Teknisk strömningslära.
    Högblom, Joakim
    AkzoNobel, Pulp and Performance Chemicals AB.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Palmlöf, Magnus
    Kessler, Vadim G.
    Swedish University of Agricultural Sciences, Department of Molecular Sciences, Uppsala BioCentre.
    Seisenbaeva, Gulaim A.
    Swedish University of Agricultural Sciences, Department of Molecular Sciences, Uppsala BioCentre.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    DTPA-Functionalized Silica Nano- and Microparticles for Adsorption and Chromatographic Separation of Rare Earth Elements2018Ingår i: ACS Sustainable Chemistry & Engineering, ISSN 2168-0485, Vol. 6, nr 5, s. 6889-6900Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Silica nanoparticles and porous microparticles have been successfully functionalized with a monolayer of DTPA-derived ligands. The ligand grafting is chemically robust and does not appreciably influence the morphology or the structure of the material. The produced particles exhibit quick kinetics and high capacity for REE adsorption. The feasibility of using the DTPA-functionalized microparticles for chromatographic separation of rare earth elements has been investigated for different sample concentrations, elution modes, eluent concentrations, eluent flow rates, and column temperatures. Good separation of the La(III), Ce(III), Pr(III), Nd(III), and Dy(III) ions was achieved using HNO3 as eluent using a linear concentration gradient from 0 to 0.15 M over 55 min. The long-term performance of the functionalized column has been verified, with very little deterioration recorded over more than 50 experiments. The results of this study demonstrate the potential for using DTPA-functionalized silica particles in a chromatographic process for separating these valuable elements from waste sources, as an environmentally preferable alternative to standard solvent-intensive processes.

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  • 13.
    Chen, Song
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Abdel-Magied, Ahmed F.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Fu, Le
    Uppsala Universitet, Department of Engineering Sciences.
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Incorporation of strontium and europium in crystals of α-calcium isosaccharinate2019Ingår i: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 364, s. 309-316Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The final repository for short-lived, low and intermediate level radioactive waste in Sweden is built to act as a passive repository. Already within a few years after closure water will penetrate the repository and conditions of high alkalinity (pH 10.5―13.5) and low temperature (< 7 °C) will prevail. The mobility of radionuclides in the repository is dependent on the radionuclides distribution between solid and liquid phases. In the present work the incorporation of strontium (II) and europium (III) in α-calcium isosaccharinate (ISA) under alkaline conditions (pH ~10) at 5 °C and 50 °C have been studied. The results show that strontium and europium are incorporated into α-Ca(ISA)2 when crystallized both at 5 °C and 50 °C. Europium is incorporated to a greater extent than strontium. The highest incorporation of europium and strontium at 5 °C rendered the phase compositions Ca0.986Eu0.014(ISA)2 (2.4% of Eu(ISA)3 by mass) and Ca0.98Sr0.02(ISA)2 (2.2% of Sr(ISA)2 by mass). XPS spectra show that both trivalent and divalent Eu coexist in the Eu incorporated samples. Strontium ions were found to retard the elongated growth of the Ca(ISA)2crystals. The incorporation of Sr2+ and Eu3+ into the solid phase of Ca(ISA)2 is expected to contribute to a decreased mobility of these ions in the repository.

  • 14.
    Chen, Song
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Wang, Shihuai
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Li, Hu
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap..
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Eu3+ doped monetite and its use as fluorescent agent for dental restorations2018Ingår i: Ceramics International, ISSN 0272-8842, E-ISSN 1873-3956, Vol. 44, nr 9, s. 10510-10516Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It is essential but challenging to distinguish the dental restorations from the surrounding teeth when removing filling materials from cavity. In this study, Eu3+ doped monetite was proposed as a fluorescent agent for dental restorations to meet this challenge. Eu3+ doped monetite with enhanced fluorescent property was obtained via a precipitation method. The presence of Eu3+ could prevent the phase transformation of brushite to monetite. However, all the brushite particles transformed to monetite at 300 °C and to tricalcium phosphate at 800 °C. The emission intensity increased with the addition of Eu3+ and reached the maximum when 12 mol% Eu3+ was added into the aqueous solution. With either 254 nm or 393 nm excitation, Eu3+ doped monetite showed the strongest fluorescence emission peaking at 616 nm and other two moderate bands peaking at 699 nm and 593 nm. The excitation spectra at the emission wavelength of 616 nm showed strong absorption peaks at 254 nm and 393 nm. We further investigate the fluorescence properties of Eu3+ doped monetite in one type of dental restorations. Glass ionomer cement with Eu3+ doped monetite exhibited clear fluoresce with origin color under UV irradiation at 254 nm, showing that Eu3+doped monetite is a promising fluorescent agent for dental restorations.

  • 15.
    Chernyshev, Alexander
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Impact of organic cement additives on the mobility of radionuclides in a radioactive waste repository2017Konferensbidrag (Refereegranskat)
  • 16.
    Chernyshev, Alexander N.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Characterization and degradation of a polyaryl ether based superplasticizer for use in concrete barriers in deep geological repositories2018Ingår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 95, s. 172-181Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Superplasticizers are important additives used in concrete barriers in geological waste repositories. Superplasticizers have been a major concern in the long-term assessments of safe geological disposal for radioactive waste since superplasticizers and their degradation products can act as complexing ligands and thereby increase the mobility of radionuclides. In this work a new type of superplasticizer, based on a polyaryl ether polymer, has been characterized. It was found that the superplasticizer combines the structural features of polycarboxylate ether based superplasticizers and sulfonated naphthalene-formaldehyde based superplasticizers and that it contains organophosphatecharged groups. A novel method for evaluating the rate of degradation of the superplasticizer under alkaline conditions was elaborated and the degradation products and rate constant of the process was determined. The results demonstrate that degradation occurs rapidly compared to the typical lifetime of a repository.

  • 17.
    Diesen, Veronica
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Jonsson, Mats
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi.
    Effects of cellulose degradation products on the mobility of Eu(III) in repositories for low and intermediate level radioactive waste2017Ingår i: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 340, s. 384-389Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The deep repository for low and intermediate level radioactive waste SFR in Sweden will contain large amounts of cellulosic waste materials contaminated with radionuclides. Over time the repository will be filled with water and alkaline conditions will prevail. In the present study degradation of cellulosic materials and the ability of cellulosic degradation products to solubilize and thereby mobilise Eu(III) under repository conditions has been investigated. Further, the possible immobilization of Eu(III) by sorption onto cement in the presence of degradation products has been investigated. The cellulosic material has been degraded under anaerobic and aerobic conditions in alkaline media (pH: 12.5) at ambient temperature. The degradation was followed by measuring the total organic carbon (TOC) content in the aqueous phase as a function of time. After 173 days of degradation the TOC content is highest in the anaerobic artificial cement pore water (1547 mg/L). The degradation products are capable of solubilising Eu(III) and the total europium concentration in the aqueous phase was 900 μmol/L after 498 h contact time under anaerobic conditions. Further it is shown that Eu(III) is adsorbed to the hydrated cement to a low extent (<9 μmol Eu/g of cement) in the presence of degradation products.

  • 18.
    Forsberg, Kerstin
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Crystallization of Metal Fluoride Hydrates from Mixed Acid Solutions2009Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In this work crystal growth and nucleation of b-FeF3×3H2O and crystallization of chromium (III), iron (III) and nickel (II) fluoride hydrates from mixed acid (1-3 mol/kg HNO3 and 1-6 mol/kg free HF) have been investigated.

    The solubility of b-FeF3×3H2O has been determined in solutions of different hydrofluoric acid (1-7mol/ kg) and nitric acid (0-7mol/ kg) concentrations at 30, 40 and 50°C. The total iron concentration at equilibrium ranges from about 1 to 35 g/kg solution. In the range of investigated conditions the solubility in terms of total iron content increases with increasing temperature and decreases with increasing concentration of hydrofluoric acid and nitric acid. The results are analysed by examining the chemical speciation in the solutions.

    The crystal growth kinetics of b-FeF3×3H2O crystals have been studied by performing seeded isothermal desupersaturation experiments in solutions of 1.5-3.0 mol/ kg nitric acid and 1.4- 5.6 mol/ kg free hydrofluoric acid at 30, 40 and 50°C. The results show that the crystal growth is surface integration controlled. When the driving force is based on a proper speciation no clear correlation of the growth rate with hydrofluoric acid or nitric acid concentration is found. The rate is about the same in industrial pickle liquor as in pure acid solutions. The growth rate at a supersaturation ratio (c(FeF3)free/cs(FeF3)free) of 2 was found to be 5.2×10-12m/s at 30°C, 7.9×10-12m/s at 40°C and 20×10-12m/s at 50°C. Thus, the crystal growth rate at 50°C is about four times higher than at 30°C. The temperature dependence of the rate constant corresponds to an activation energy of 55kJ/ mol.

    Crystallization from solutions supersaturated with both Cr(III) and Fe(III) has been investigated and it has been observed that Fe(III) and Cr(III) crystallizes in the form of Cr(Fe)F3×3H2O which is isostructural with CrF3×3H2O. Iron(III) and nickel(II) crystallizes into an unidentified fluoride hydrate crystal.

    The crystal growth rate of CrF3×3H2O at 50°C is about the same as the growth rate of b-FeF3×3H2O crystals.

  • 19.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Valorisation of phosphate rock by hydrometallurgical processing2017Ingår i: 16ème Congrès de la Société Française de Génie des Procédés SFGP (16th Congress of the French Chemical Engineering Society), 2017Konferensbidrag (Refereegranskat)
  • 20.
    Forsberg, Kerstin M.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Mohammadi, M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Ghafarnejad Parto, S.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Martínez de la Cruz, Joaquin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Fredriksson, A.
    LKAB.
    Recovery of REE from an apatite concentrate2014Konferensbidrag (Refereegranskat)
  • 21.
    Forsberg, Kerstin M.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk apparatteknik.
    Rasmuson, Åke C.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    The influence of hydrofluoric acid and nitric acid on the growth kinetics of iron(III) fluoride trihydrate2015Ingår i: Journal of Crystal Growth, ISSN 0022-0248, E-ISSN 1873-5002, Vol. 423, s. 16-21Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The influence of hydrofluoric acid and nitric acid concentration on the growth rate of beta-FeF3 center dot 3H(2)O crystals has been studied in different hydrofluoric acid (4.7-10.7 mol/(kg H2O)) and nitric acid (2.1-4.6 mol/(kg H2O)) mixtures at 50 degrees C. Seeded desupersaturation experiments were performed and the results were evaluated by considering the chemical speciation using two different speciation programs. The growth rate at 50 degrees C at a supersaturation ratio of 2, expressed in terms of free FeF3, was found to be in the range of (0.4-3.8) x 10(-11) m/s. The growth rate order was found to be two or higher in all experiments. The low growth rate and high growth rate order indicate that the growth rate is governed by the surface integration step. The growth rate was found to be independent of variations in acid concentrations: this is in accordance with the assumption of a surface integration controlled growth rate.

  • 22.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Mohammadi, M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Ghafarnejad Parto, S.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Alemrajabi, Mahmoud
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Korkmaz, Kivanc
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Martínez De La Cruz, Joaquin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Novel hydrometallurgical methods for recovery and separation of REE2014Konferensbidrag (Refereegranskat)
  • 23.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemivetenskap (CHE).
    Nenert, G.
    PANalytical BV, NL-7602 EA Almelo, Netherlands..
    Tao, T.
    Univ Houston, Dept Chem, Houston, TX 77204 USA..
    Halasyamani, P. S.
    Univ Houston, Dept Chem, Houston, TX 77204 USA..
    Crystal structure of hydrated fluorides MF2 center dot 4H(2)O (M=Zn, Ni, Co): a combined approach2015Ingår i: Acta Crystallographica Section A: Foundations and Advances, ISSN 2053-2733, Vol. 71, s. S484-S484Artikel i tidskrift (Refereegranskat)
  • 24.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Nénert, G.
    Malvern Panalytical.
    Martineau, C.
    Institut Lavoisier de Versailles.
    Tao, T.
    University of Houston.
    Halasyamani, Shiv
    University of Houston.
    Crystal structure of hydrated fluorides M F 2 ·4H 2 O ( M = Zn, Ni, Co): a combined approach2015Konferensbidrag (Refereegranskat)
  • 25.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Rasmuson, Åke
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Crystal growth of iron(III) flouride trihydrate in mixed acidManuskript (preprint) (Övrigt vetenskapligt)
  • 26.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Rasmuson, Åke
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Crystallization in hydrofluoric acid and nitric acid solutions containing iron(III), chronium(III) and nickel(II).Manuskript (preprint) (Övrigt vetenskapligt)
  • 27.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Rasmuson, Åke
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Crystallization of metal fluoride hydrates from mixed hydrofluoric and nitric acid solutions, Part I: Iron (III) and Chromium (III)2010Ingår i: Journal of Crystal Growth, ISSN 0022-0248, E-ISSN 1873-5002, Vol. 312, nr 16-17, s. 2351-2357Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Crystallization from hydrofluoric acid/nitric acid solutions supersaturated with Fe(III) and Cr(III) has been investigated. Iron and chromium crystallizes into a solid solution in the form of Cr(Fe)F-3 center dot 3H(2)O, which is isostructural with CrF3 center dot 3H(2)O and alpha-FeF3 center dot 3H(2)O. By seeded isothermal desupersaturation experiments, the growth rate of beta-FeF3 center dot 3H(2)O crystals at 50 degrees C has been studied in hydrofluoric acid and nitric acid solutions containing Cr(III). It is found that the growth rate of beta-FeF3 center dot 3H(2)O is essentially uninfluenced by the presence of 5 g/kg Cr(III). At 50 degrees C and a supersaturation ratio of 2 (c(FeF3)(free)/c(s)(FeF3)(free)), the growth rate is (0.8-2.2) x 10(-11) m/s in 3 mol/(kg solution) HFfree and 3 mol/(kg solution) HNO3.

  • 28.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Rasmuson, Åke
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Crystallization of metal fluoride hydrates from mixed hydrofluoric and nitric acid solutions, part II: Iron (III) and nickel (II)2010Ingår i: Journal of Crystal Growth, ISSN 0022-0248, E-ISSN 1873-5002, Vol. 312, nr 16-17, s. 2358-2362Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Crystallization of nickel fluoride hydrate from mixed pickle acid and the influence of Ni(II) on growth rate of beta-FeF3 center dot 3H(2)O have been studied. Iron and nickel crystallize into an unidentified Fe/Ni fluoride hydrate crystal having the overall mol ratio of Ni, Fe, and F equal to 1:2:8, which is in accordance with the number of fluoride ions needed to balance the positive charges of Ni and Fe. The most probable empirical formula of this material is (FeF3)(2)NiF2(H2O)(6-10). By seeded isothermal desupersaturation experiments, growth rate of beta-FeF3 center dot 3H(2)O crystals at 50 degrees C has been studied in a hydrofluoric acid and nitric acid solution containing Ni(II). It is found that the growth rate of beta-FeF3 center dot 3H(2)O is essentially uninfluenced by the presence of 4 g/kg Ni(II).

  • 29.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Rasmuson, Åke C
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Crystal growth kinetics of iron fluoride trihydrate2006Ingår i: Journal of Crystal Growth, ISSN 0022-0248, E-ISSN 1873-5002, Vol. 296, nr 2, s. 213-220Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Crystal growth of beta-FeF3 • 3H(2)O has been investigated in mixtures of 3 mol kg(-1) hydrofluoric acid and 3 mol kg(-1) nitric acid at 30, 40 and 50 degrees C. Seeded isothermal desupersaturation experiments have been performed in the range: 1.3 < S < 3.6. Solution samples were analysed for total iron concentration with inductively coupled plasma atomic emission spectroscopy. The true supersaturation driving force was estimated by a proper speciation using the software SSPEC using appropriate stability constants. Growth rate parameters of the BCF surface diffusion growth rate equation and the empirical power-law equation have been estimated by fitting the supersaturation balance equation using a nonlinear optimization procedure. The results show that the growth rate is surface integration controlled. The growth rate at a supersaturation ratio of 2 was found to be 3.5 x 10(-12) m s(-1) at 30 degrees C, 7.4 x 10(-12) m s(-1) at 40 degrees C and 16 x 10(-12) m s(-1) at 50 degrees C. The activation energy of the rate constant of crystal growth was found to be 61 kJ mol(-1). .

  • 30.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Rasmuson, Åke C
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Recycling of waste pickle acid by precipitation of metal fluoride hydrates2007Ingår i: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 20, nr 9, s. 950-955Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Stainless steel is pickled in mixed acid solutions (1-3 M HNO3 and 0.5-4 M HF). The spent solution is usually neutralized with lime, and in Sweden about 18,000 tons/yr of metal hydroxide sludge is disposed as landfill waste. We are developing a cost-saving and environmentally friendly process, involving crystallization of beta-FeF3 . 3H(2)O, where the metal content is recovered and the acid is recycled. Iron has been successfully separated from spent pickle bath solutions by precipitation of beta-FeF3 . 3H(2)O in a continuous crystallizer (10 L scale) where the solution is concentrated by nanofiltration. The crystal growth rate of beta-FeF3 . 3H(2)O has been determined in industrial pickle bath solutions at 50 degrees C and the results have been compared to previous measurements in pure HF/HNO3 solutions prepared in the laboratory. The growth rate of beta-beta eF(3) . 3H(2)O crystals at 50 degrees C is in the order of 10(-11) m/s in both industrial and pure acid mixtures.

  • 31.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Rasmuson, Åke Christoffer
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Precipitation from HF and HNO3 solutions containing iron (III), nickel (II) and chromium (III)2008Ingår i: Proc. 17’th International Symposium on Industrial Crystallization / [ed] JP Janssens; J Ulrich, 2008, s. 1175-1180Konferensbidrag (Refereegranskat)
  • 32.
    Forsberg, Kerstin
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Rodríguez Varela, Raquel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Martínez, Joaquin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Kloo, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Processing of a rare earth element concentrate by hollow fibre supported liquid membrane extraction2017Konferensbidrag (Refereegranskat)
  • 33.
    Hammer-Olsson, Roy
    et al.
    Perstorp AB.
    Jansson, Inger
    Perstorp AB.
    Hultén, Felix
    Perstorp AB.
    Forsberg, Kerstin
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Rasmuson, Åke Christoffer
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Method of purifying potassium hydroxide2007Patent (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Method of purifying potassium hydroxide comprising (a) providing a solution of saturated potassium hydroxide solution having a temperature in the range from about -25 to about 60 0C (b) controling the temperature of the solution in such a way that the variation in temperature is in a range from about 0 to about 5 °C/h to form crystals of potassium hydroxide (c) separating the crystals from the solution.

  • 34.
    Kaya, Şerif
    et al.
    Middle East Technical University.
    Peters, Edward Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Dittrich, Carsten
    MEAB Chemie Technik GmbH.
    Stopic, Srecko
    RWTH Aachen University.
    Friedrich, Bernd
    RWTH Aachen University.
    Scandium Recovery from an Ammonium Fluoride Strip Liquor by Anti-Solvent Crystallization2018Ingår i: Metals, ISSN 2075-4701, Vol. 8, nr 10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, the crystallization of scandium from ammonium fluoride strip liquor, obtained by solvent extraction, was investigated using an anti-solvent crystallization technique. Acetone, ethanol, methanol and isopropanol were added individually to the strip liquor as the anti-solvent and scandium was precipitated and obtained in the form of (NH4)3ScF6 crystals. The results show that scandium can be effectively crystallized from the strip liquor to obtain an intermediate, marketable scandium product. Yields greater than 98% were obtained using an anti-solvent to strip liquor volumetric ratio of 0.8. Acetone had the least performance at lower anti-solvent to strip liquor volumetric ratios, possibly due to its limited H bonding capability with water molecules when compared to alcohols.

  • 35.
    Korkmaz, Kivanc
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Alemrajabi, Mahmood
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Recovery of rare earth elements from spent NiMH HEV batteries via selective roasting and water leaching2017Konferensbidrag (Refereegranskat)
  • 36.
    Korkmaz, Kivanc
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Teknisk strömningslära.
    Alemrajabi, Mahmood
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Teknisk strömningslära.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Recoveries of Valuable Metals from Spent Nickel Metal Hydride Vehicle Batteries via Sulfation, Selective Roasting, and Water Leaching2018Ingår i: Journal of Sustainable Metallurgy, ISSN 2199-3823, Vol. 4, nr 3, s. 313-325Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The recoveries of rare earth elements (REEs), nickel, and cobalt from hybrid electric vehicle batteries by sulfation, selective roasting, and water leaching have been studied. The cathode and anode materials of a Panasonic Prismatic Module nickel metal hydride (NiMH) battery were used in the study. The optimal conditions for each step of the process were determined by performing lab-scale experiments. It was found that 8 mol/L of sulfuric acid was sufficient for the sulfation with a solid-to-liquid ratio of 1/5. The optimal roasting conditions was determined to be 850 °C for 2 h. Under optimal conditions, 96% of the REEs could be obtained in the aqueous phase with negligible contamination of Ni and Co. The Ni and Co remained in solid phase as oxides together with traces of aluminum, zinc, and iron oxides. This method provides a way for the separation of the REEs from nickel, cobalt, and other elements present in the NiMH battery, into a leachate suitable for further processing.

  • 37.
    Korkmaz, Kivanc
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Alemrajabi, Mahmood
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Separation of Valuable Elements from NiMH Battery Leach Liquor via Antisolvent Precipitation2020Ingår i: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 234, artikel-id 115812Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rare earth elements (REE) have been selectively recovered from NiMH battery leach liquors by antisolvent precipitation. The active anode material was leached using sulfuric acid. The REE were then separated from the other elements by precipitation as sulfates after addition of either ethanol or 2-propanol (antisolvent). In a second step, Ni and Co are separated as sulfates by the same technique. The concentration of elements in different acid alcohol mixtures at 25 degrees C and -10 degrees C respectively are presented as a function of time after addition of the alcohol, and the optimum conditions for separation of the REE in pure form are presented. Under optimum conditions, 5.6 mol/L (Organic/Aqueous (O/A) volumetric ratio = 0.7) of 2-propanol at 25 degrees C, 82% of the REE have precipitated 3 h after addition of the antisolvent and the purity is 99.9%.

  • 38.
    Korkmaz, Kivanc
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Alemrajabi, Mahmood
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Sustainable Hydrometallurgical Recovery of Valuable Elements from Spent Nickel-Metal Hydride HEV Batteries2018Ingår i: Metals, ISSN 2075-4701, Vol. 8, nr 12Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the present study, the recovery of valuable metals from a Panasonic Prismatic Module 6.5 Ah NiMH 7.2 V plastic casing hybrid electric vehicle (HEV) battery has been investigated, processing the anode and cathode electrodes separately. The study focuses on the recovery of the most valuable compounds, i.e., nickel, cobalt and rare earth elements (REE). Most of the REE (La, Ce, Nd, Pr and Y) were found in the anode active material (33% by mass), whereas only a small amount of Y was found in the cathode material. The electrodes were leached in sulfuric acid and in hydrochloric acid, respectively, under different conditions. The results indicated that the dissolution kinetics of nickel could be slow as a result of slow dissolution kinetics of nickel oxide. At leaching in sulfuric acid, light rare earths were found to reprecipitate increasingly with increasing temperature and sulfuric acid concentration. Following the leaching, the separation of REE from the sulfuric acid leach liquor by precipitation as NaREE (SO4)(2)center dot H2O and from the hydrochloric acid leach solution as REE2 (C2O4)(3)center dot xH(2)O were investigated. By adding sodium ions, the REE could be precipitated as NaREE (SO4)2 center dot H2O with little loss of Co and Ni. By using a stoichiometric oxalic acid excess of 300%, the REE could be precipitated as oxalates while avoiding nickel and cobalt co-precipitation. By using nanofiltration it was possible to recover hydrochloric acid after leaching the anode material.

  • 39.
    Korkmaz, Kivanc
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Hydrometallurgical process development for recycling of spent NiMH battery systems from the transport sector2016Konferensbidrag (Refereegranskat)
  • 40.
    Larsson, M
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Yan, J.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Liu, Longcheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Storm water issues in biomass-fired combined heat and power plants2015Konferensbidrag (Refereegranskat)
  • 41.
    Larsson, Magnus
    et al.
    KTH.
    Yan, Jinying
    KTH. Vattenfall AB, Sweden.
    Nordenskjöld, C.
    Forsberg, Kerstin
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk apparatteknik.
    Liu, Longcheng
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk apparatteknik.
    Characterisation of stormwater in biomass-fired combined heat and power plants: Impact of biomass fuel storage2016Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 170, s. 116-129Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Characteristics of stormwater in industrial areas are evaluated, specifically based on a biomass-fired combined heat and power (CHP) plant with on-site biomass fuel storage. An evaluation method is developed to combine general methodology applied for stormwater characterisation with the on-site features of the biomass-fired CHP plant. Investigations were carried out through on-site monitoring and laboratory experiments with the defined methodology. Recycled wood chips as biomass fuel currently used in Swedish biomass-fired CHP plants have been used as an example for this study. The impacts of outdoor biomass fuel storage have been analysed for both runoff water quantity and quality. The results indicate that the properties of stored biomass fuels will significantly affect the runoff quantity by its water absorption capability. The overall runoff quality is highly depended on precipitation intensity and the runoff volume from the biomass storage piles, which is influenced by the water retention capacity and leaching ability of biomass fuels. The practical data and information presented in this paper can be used to understand the principal issues and the most important factors for internal control of contamination sources in order to achieve sustainable Energy-Water systems for bioenergy conversion in biomass-fired CHP plants.

  • 42.
    Martinez, Joaquin
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Rodriguez Varela, Raquel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Rasmuson, Åke C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Factors Influencing Separation Selectivity of Rare Earth Elements in Flat Sheet Supported Liquid Membranes2018Ingår i: Chemical Engineering Science, ISSN 0009-2509, E-ISSN 1873-4405, Vol. 191, s. 134-155Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Separation selectivity of the mixture Yttrium-Neodymium-Dysprosium using Bis (2-ethylhexyl) hydrogen phosphate (D2EHPA) as extractant in a flat sheet supported liquid membrane was studied by simulations. A new definition of selectivity and a diffusional-kinetic transient model were used in the calculations. Resistance distribution between the phases, stripping phase pH, extractant concentration and initial feed concentration have great influence on selectivity and process time and their appropriate management would improve separation. The analysis of selectivity using the present model would be a useful tool to design a multistage process aimed at the separation of a multicomponent mixture of rare earth elements into its constituents.

  • 43.
    Mohammadi, Maryam
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk teknologi.
    Forsberg, Kerstin
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk apparatteknik.
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi.
    De La Cruz, Joaquin Martinez
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk teknologi.
    Rasmuson, Åke
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Teknisk strömningslära.
    Separation of Nd(III), Dy(III) and Y(III) by solvent extraction using D2EHPA and EHEHPA2015Ingår i: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158, Vol. 156, s. 215-224Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The equilibrium separation of trivalent rare earth elements (Nd(III), Dy(III), and Y(III)) from hydrochloric acid solution by di-(2-ethylhexyl) phosphoric acid (D2EHPA) and 2-ethylhexylphosphonic acid mono-2-ethyl hexyl ester (EHEHPA) separately and in mixtures has been studied. The effect of extractant concentration, extractant mixture composition and solution acidity has been investigated. The results show that a mixture of D2EHPA and EHEHPA provide a better separation of Y(III) from Dy(III) when the total extractant concentration is 0.06 and 0.09 mol/L, while the separation is better using pure EHEHPA at higher extractant concentration (0.15 mol/L). The separation of Nd(III) from Y(III) and Dy(III) is higher using pure D2EHPA (0.06 and 0.15 mol/L). The results show that for the complexation of the Nd(III) ions approx. 1-2 hydrogen ions/rare earth element (REE) ion are released to the aqueous phase upon binding approximately 1 extractant dimer on average. For the complexation of Y(III) and Dy(III) ions 2-3 hydrogen ions are released upon binding approximately two extractant dimers on average. Accordingly, under the conditions of this work the complexation involves not only extractant molecule dimers but also monomers or aggregated REE species to some extent, and a fraction of the REE is extracted as chloride complexes. (C) 2015 Elsevier B.V. All rights reserved.

  • 44.
    Nenert, Gwilherm
    et al.
    PANalytical BV, NL-7602 EA Almelo, Netherlands..
    Fabelo, O.
    Inst Laue Langevin, F-38000 Grenoble, France..
    Forsberg, Kerstin
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Colin, C. V.
    Inst Neel, F-38042 Grenoble, France..
    Rodriguez-Carvajal, J.
    Inst Laue Langevin, F-38000 Grenoble, France..
    Structural and magnetic properties of the low dimensional fluoride beta-FeF3 center dot 3H(2)O2015Ingår i: Acta Crystallographica Section A: Foundations and Advances, ISSN 2053-2733, Vol. 71, s. S98-S98Artikel i tidskrift (Refereegranskat)
  • 45. Nenert, Gwilherm
    et al.
    Fabelo, Oscar
    Forsberg, Kerstin
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk apparatteknik.
    Colin, Claire V.
    Rodriguez-Carvajal, Juan
    Structural and magnetic properties of the low-dimensional fluoride beta-FeF3(H2O)(2)center dot H2O2015Ingår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 44, nr 31, s. 14130-14138Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have reinvestigated the crystal structure of the low-dimensional fluoride beta-FeF3(H2O)(2)center dot H2O using high resolution neutron and X-ray diffraction data. Moreover we have studied the magnetic behavior of this material combining medium resolution and high flux neutron powder diffraction together with magnetic susceptibility measurements. This fluoride compound exhibits vertex-shared 1D Fe3+ octahedral chains, which are extended along the c-axis. The magnetic interactions between adjacent chains involve super-superexchange interactions via an extensive network of hydrogen bonds. This interchain hydrogen bonding scheme is sufficiently strong to induce a long range magnetic order appearing below T = 20(1) K. The magnetic order is characterized by the propagation vector k = (0, 0, 1/2), giving rise to a strictly antiferromagnetic structure where the Fe3+ spins are lying within the ab-plane. Magnetic exchange couplings extracted from magnetization measurements are found to be J(II)/k(b) = -18 K and J(perpendicular to)/k(b) = -3 K. These values are in good agreement with the neutron diffraction data, which show that the system became anti-ferromagnetically ordered at ca. T-N = 20(1) K.

  • 46.
    Nénert, G.
    et al.
    Malvern Panalytical.
    Fabelo, O.
    Institut Laue-Langevin.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Colin, C. V.
    Université Grenoble Alpes.
    Rodríguez-Carvajal, J.
    Institut Laue-Langevin.
    Structural and magnetic properties of the low dimensional fluoride β-FeF3.3H2O2015Konferensbidrag (Refereegranskat)
  • 47.
    Peters, Edward
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Dittrich, C.
    MEAB Chemie Technik GmbH.
    Kaya, S.
    MEAB Chemie Technik GmbH.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Crystallization of a pure scandium phase from solvent extraction strip liquors2018Konferensbidrag (Refereegranskat)
  • 48.
    Peters, Edward
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Kaya, S.
    Dittrich, C.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Recovery of scandium by crystallization techniques2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    Bauxite residues, so called red mud, can be processed to recover various valuable end products, whilst reducing the environmental impact of the waste. Scandium is one of the valuable elements in bauxite residues. It is possible to extract and enrich scandium from red mud by leaching and solvent extraction. Scandium can then be recovered from the pregnant strip liquor by crystallisation. Different crystallisation techniques can be used to generate the supersaturation required for scandium to crystallise out as a salt. In the present work, the crystallisation of an ammonium scandium fluoride phase by cooling and anti-solvent crystallisation techniques is presented with respect to crystal quality (purity, size and morphology) and yield. 

  • 49.
    Peters, Edward Michael
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Co-precipitation of impurity (Ti, Fe, Zr, U) phases during the recovery of (NH4)3ScF6 from strip liquors by anti-solvent crystallization2020Ingår i: Rare Metal Technology 2020 / [ed] Azimi, G., Forsberg, K.M., Oishi, T., Kim, H., Alam, S., Baba, A.A., Springer Nature, 2020Konferensbidrag (Refereegranskat)
  • 50.
    Peters, Edward Michael
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Kaya, Şerif
    Middle East Technical University, Mining Engineering Department, Ankara, Turkey.
    Dittrich, Carsten
    MEAB Chemie Technik GmbH, Aachen, Germany.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Recovery of scandium by crystallization techniques2019Ingår i: Journal of Sustainable Metallurgy, ISSN 2199-3823, Vol. 5, nr 1, s. 48-56Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Bauxite residues, i.e., red mud, can be processed to recover various valuable end products, while reducing the environmental impact of the waste. Scandium is one of the valuable elements in bauxite residues. It is possible to extract and enrich scandium from red mud by leaching and solvent extraction. Scandium can then be recovered from the pregnant strip liquor by crystallization. Different crystallization techniques can be used to generate the supersaturation required for scandium to crystallize out as a salt. In the present study, the crystallization of an ammonium scandium fluoride phase by cooling and antisolvent crystallization techniques is presented. Cooling crystallization gave a low yield of ammonium scandium hexafluoride, (NH4)3ScF6, below 50% at the lowest temperature of 1 °C investigated. Antisolvent crystallization using ethanol gave almost complete recovery with precipitation efficiency greater than 98% for an ethanol-to-strip liquor volumetric ratio of 0.8. Solubility data of (NH4)3ScF6 under different temperatures and in different ethanol–strip liquor mixtures is herein presented. The product obtained by antisolvent crystallization had very minute crystals (< 2 µm) due to the high supersaturation generated upon adding ethanol to the strip liquor, while it was easier to obtain larger crystals by cooling crystallization. Fe and Ti impurities were detected in the solid product, and an insight into the mechanism of impurity uptake is discussed.

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