Change search
Refine search result
123 1 - 50 of 103
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Ahuja, D.
    et al.
    Synthesis and Solid State Pharmaceutical Centre, Department of Chemical Sciences, Bernal Institute, University of Limerick, Castletroy, Co., Limerick, Ireland.
    Bannigan, P.
    Synthesis and Solid State Pharmaceutical Centre, Department of Chemical Sciences, Bernal Institute, University of Limerick, Castletroy, Co., Limerick, Ireland.
    Rasmuson, Åke Christoffer
    Synthesis and Solid State Pharmaceutical Centre, Department of Chemical Sciences, Bernal Institute, University of Limerick, Castletroy, Co., Limerick, Ireland.
    Study of three solvates of sulfamethazine2017In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 19, no 43, p. 6481-6488Article in journal (Refereed)
    Abstract [en]

    Three novel solvates of sulfamethazine (SMT), an anti-microbial and anti-infective sulfonamide drug with the solvents-dimethylacetamide, dimethylformamide and dimethyl sulfoxide have been identified and characterized by analytical techniques including differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction and Raman spectroscopy. All three are 1:1 solvates. Crystal structure analysis revealed N-H-O type intermolecular hydrogen bonding interactions between SMT and the solvent imparting stability to the solvate structure. Thermal analysis measurements for the stoichiometry of the solvates were in good agreement with the single crystal data. The solubility of the solvates in their respective solvents at 25 °C has been determined. © 2017 The Royal Society of Chemistry.

  • 2.
    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.

  • 3.
    Alemrajabi, M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Forsberg, Kerstin
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Korkmaz, Kivanc
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Isolation of rare earth element phosphate precipitate in the nitrophosphate process for manufacturing of fertilizer2016Conference paper (Refereed)
  • 4.
    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)
  • 5.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Forsberg, Kerstin
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Korkmaz, Kivanc
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Rasmuson, Åke C.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Isolation of rare earth element phosphate precipitate in the nitrophosphate process for manufacturing of fertilizer2016In: IMPC 2016 - 28th International Mineral Processing Congress, Canadian Institute of Mining, Metallurgy and Petroleum , 2016Conference paper (Refereed)
    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. 

  • 6.
    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)
  • 7.
    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.

  • 8.
    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 productionManuscript (preprint) (Other academic)
  • 9.
    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.

  • 10.
    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)
  • 11.
    Ashour, Radwa
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering. 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, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Högblom, Joakim
    AkzoNobel, Pulp and Performance Chemicals AB.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    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, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    DTPA-Functionalized Silica Nano- and Microparticles for Adsorption and Chromatographic Separation of Rare Earth Elements2018In: ACS Sustainable Chemistry & Engineering, ISSN 2168-0485, Vol. 6, no 5, p. 6889-6900Article in journal (Refereed)
    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.

  • 12. Bodnar, K.
    et al.
    Hudson, S. P.
    Rasmuson, Åke C.
    Stepwise use of additives for improved control over formation & stability of mefenamic acid nanocrystals produced by antisolvent precipitation2017In: Crystal Growth and Design, Vol. 17, no 2, p. 454-466Article in journal (Refereed)
    Abstract [en]

    A method of introducing different additives at different times during the process, i.e., stepwise addition of additives, has been developed to produce stable nanoparticles of mefenamic acid (MEF) by antisolvent precipitation. In the absence of additives, at optimized conditions, MEF crystals were prepared in the size range of 0.25-3.05 μm; however, these crystals formed large agglomerates in suspension (∼12.1 μm). In the presence of all additives evaluated, with the exception of hydroxypropylmethylcellulose (HPMC), smaller particles were produced in suspension, the most effective additive being sodium docusate (DOSS), generating nanoparticles, ∼312 nm in size. However, the particle size was not stable but increased to ∼788 nm after 80 min in suspension associated with a polymorphic transformation. Combining the initial use of DOSS with the subsequent addition of HPMC or poly(vinyl alcohol) (PVA) allowed for the production of a stable suspension of MEF nanocrystals (∼317 and ∼311 nm, respectively). The interaction of HPMC and PVA with MEF particles delayed polymorphic transformation by inhibiting nucleation and/or growth of the stable MEF polymorph. The results show that using stepwise addition of additives, separately targeting nucleation and crystal growth/phase transformation, can improve the manufacturing and stabilization of nanocrystal suspensions. 

  • 13. Bodnár, K.
    et al.
    Hudson, S. P.
    Rasmuson, Åke C.
    Promotion of Mefenamic Acid Nucleation by a Surfactant Additive, Docusate Sodium2019In: Crystal Growth and Design, Vol. 19, no 2, p. 591-603Article in journal (Refereed)
    Abstract [en]

    The influence of docusate sodium (DOSS) on the nucleation of mefenamic acid (MEF) has been studied in different dimethylacetamide (DMA)-water mixtures. A series of induction time experiments were conducted under moderate supersaturations, varying the solvent composition and the concentration of DOSS. In 40% DMA-60% water, the presence of 0.1 and 0.2 mg/mL DOSS increased the nucleation rate. Evaluating the results by the classical nucleation theory reveals that the pre-exponential factor (A) increases by approximately 50% while the interfacial energy is essentially uninfluenced. It is also found that the crystal growth rate becomes higher in the presence of DOSS. It is thus hypothesized that transport and desolvation of MEF molecules are facilitated in the presence of DOSS. With increasing amount of DMA in the binary solvent mixture, the influence of DOSS appears to decrease. 

  • 14. Bohlin, M.
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Application of controlled cooling and seeding in batch crystallization1992In: The Canadian Journal of Chemical Engineering, Vol. 70, no 1, p. 120-126Article in journal (Refereed)
  • 15. Bohlin, M.
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Importance of Macromixing in Batch Cooling Crystallization1996In: AIChE Journal, Vol. 42, no 3, p. 691-699Article in journal (Refereed)
  • 16. Bohlin, M.
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Modeling of growth rate dispersion in batch cooling crystallization1992In: AIChE Journal, Vol. 38, no 12, p. 1853-1863Article in journal (Refereed)
  • 17. Cheuk, D.
    et al.
    Khamar, D.
    McArdle, P.
    Rasmuson, Åke Christoffer
    Univ Limerick, Dept Chem & Environm Sci, Mat & Surface Sci Inst, Synth & Solid State Pharmaceut Ctr,.
    Solid Forms, Crystal Habits, and Solubility of Danthron2015In: Journal of Chemical and Engineering Data, Vol. 60, no 7, p. 2110-2118Article in journal (Refereed)
    Abstract [en]

    The polymorphism, crystal habits, and solubility of 1,8-dihydroxyanthraquinone (danthron) were investigated in acetic acid, acetone, acetonitrile, n-butanol, and toluene. The solubility was determined for the commercially available form (FI) from 293.15 K to 318.15 K. by the gravimetric method. The influence of solvents on crystal habit and polymorphic form has been investigated. Three different crystal habits of danthron were obtained from slow evaporation and cooling experiments. By evaporation, thin squares of FI were obtained from n-butanol and toluene solutions while both FT and fine needles of FIT were obtained from acetone and acetonitrile solutions. In addition, needle-shaped solvate crystals were obtained from acetic acid solutions and the structure of the solvate was solved by single crystal X-ray diffraction. From cooling crystallization experiments, mixtures of FI and FIT were often obtained from various solvents, but FT and FIT possess distinct habits which can be easily distinguished by visual comparison. Slurry conversion experiments have established that FT is the thermodynamically stable polymorph of danthron at ambient conditions. Differntial scanning calorimetry (DSC) and high-temperature powder X-ray diffraction (PXRD) have shown that both FI and FII will transform into a high-temperature form (FIV) around 435 K to 439 K before this form melts at 468.5 K. FI, FIT, and FIV have been characterized by transmission and high-temperature PXRD, scanning electron microscopy, infrared spectrometry, Raman spectrometry, thermogravimetric analysis, and DSC. The solubility of danthron FI in the pure organic solvents of the present work and in the temperature range investigated is below 4.3 % by weight and decreases in the order toluene, acetone, acetonitrile, and n-butanol.

  • 18. Croker, D. M.
    et al.
    Davey, R. J.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering. Univ Limerick, Mat & Surface Sci Inst, Dept Chem & Environm Sci.
    Seaton, C. C.
    Nucleation in the p-toluenesulfonamide/triphenylphosphine oxide co-crystal system2013In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 13, no 8, p. 3754-3762Article in journal (Refereed)
    Abstract [en]

    Nucleation has been studied in pure co-crystal and mixed co-crystal phase regions of the ternary phase diagram (TPD) in acetonitrile at 20 C using cooling crystallization experiments. Direct nucleation of each of the co-crystal phases in this system was independently observed in regions of the TPD where each is stable. In mixed regions, regions where either a co-crystal and a coformer, or both co-crystals, are stable, the phase that initially nucleated was a function of the mass composition in that region. The relative amount of each phase nucleating could be controlled by adjusting the relative mass fraction of each component. The kinetic return to equilibrium was also observed as the systems were held over time, with the selected mass fractions always returning to the equilibrium dictated by the TPD after 24 h

  • 19. Croker, D. M.
    et al.
    Davey, R. J.
    Rasmuson, Åke Christoffer
    Univ Limerick, Mat & Surface Sci Inst, Dept Chem & Environm Sci.
    Seaton, C. C.
    Solution mediated phase transformations between co-crystals2013In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 15, no 11, p. 2044-2047Article in journal (Refereed)
    Abstract [en]

    A solution mediated transformation between two co-crystal phases has been observed for the p-toluensulfonamide-triphenylphosphine oxide co-crystal system. This system has two known co-crystals with 1 : 1 and 3 : 2 stoichiometry respectively, and the ternary phase diagram (TPD) for the system has been determined in acetonitrile previously. By manipulating the solution composition in this solvent to a region of the TPD where the 1 : 1 co-crystal is stable, the 3 : 2 co-crystal could be observed to convert to the 1 : 1 co-crystal. The corresponding transformation was true for the 1 : 1 co-crystal in a region of the TPD where the 3 : 2 co-crystal is stable; the 1 : 1 co-crystal converted to the 3 : 2 co-crystal.

  • 20. Croker, D. M.
    et al.
    Kelly, D. M.
    Horgan, D. E.
    Hodnett, B. K.
    Lawrence, S. E.
    Moynihan, H. A.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering. University of Limerick.
    Demonstrating the Influence of Solvent Choice and Crystallization Conditions on Phenacetin Crystal Habit and Particle Size Distribution2015In: Organic Process Research & Development, ISSN 1083-6160, E-ISSN 1520-586X, Vol. 19, no 12, p. 1826-1836Article in journal (Refereed)
    Abstract [en]

    Phenacetin was used as a model pharmaceutical compound to investigate the impact of solvent choice and crystallization conditions on the crystal habit and size distribution of the final crystallized product. The crystal habit of phenacetin was explored using crash-cooling crystallization (kinetically controlled) and slow evaporative crystallization (thermodynamically controlled) in a wide range of organic solvents. In general, a variety of needle-type shapes (needles, rods, or blades) were recovered from fast-cooling crystallizations, in contrast to hexagonal blocks obtained from slow evaporative crystallizations. The solubility of phenacetin was measured in five solvents from 10-70 degrees C to allow for the design of larger-scale crystallization experiments. Supersaturation and the nucleation temperature were independently controlled in isothermal desupersaturation experiments to investigate the impact of each on crystal habit and size. The crystal size (needle cross-sectional area) decreased with increasing supersaturation because of higher nucleation rates at higher supersaturation, and elongated needles were recovered: Increasing the nucleation temperature resulted in the production of larger crystals with decreased needle aspect ratios. Antisolvent phenacetin crystallizations were developed for three solvent/antisolvent systems using four different antisolvent addition rates to simultaneously probe the crystal habit and size of the final product. In general, increasing the antisolvent addition rate, associated with increased rate of generation of supersaturation, resulted in the production of shorter needle crystals.

  • 21. Croker, D. M.
    et al.
    Rasmuson, Åke Christoffer
    University of Limerick.
    Isothermal suspension conversion as a route to cocrystal production: One-pot scalable synthesis2014In: Organic Process Research & Development, ISSN 1083-6160, E-ISSN 1520-586X, Vol. 18, no 8, p. 941-946Article in journal (Refereed)
    Abstract [en]

    Isothermal suspension conversion is presented as a suitable method for the manufacture of pure cocrystal products once the ternary phase diagram (TPD) for the cocrystal system in the desired solvent is available. One:one and 3:2 cocrystals of p-toluenesulphonamide/triphenylphosphine oxide were produced in acetonitrile and dichloromethane using this method. Eight individual batches of product were prepared with complete conversion to pure product achieved in seven batches. Product recovery (77-99%), reaction conversion (17-89%), and volumetric productivity (0.03-0.63 g/cm(3)) were calculated for each product batch. These parameters are essentially determined by the batch operating mass fraction composition selected from the TPD, allowing for tailoring of processing conditions to suit process requirements and capabilities by careful selection of the optimum operating mass fraction composition.

  • 22.
    Croker, Denise
    et al.
    Chemical and Environmental Science, University of Limerick, Ireland.
    Foreman, Michael
    University of Cork, Ireland.
    Hogan, Bridget
    University of Cork, Ireland.
    Maguire, Nuala
    University of Cork, Ireland.
    Curtis, Elcoate
    University of Cork, Ireland.
    Hodnett, Kieran
    Chemical and Environmental Science, University of Limerick, Ireland.
    Maguire, Anita
    University of Cork, Ireland.
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena. Univ Limerick, Ireland.
    Lawrence, Simon
    University of Cork, Ireland.
    Understanding the p-toluenesulfonamide / triphenylphosphine oxide crystal chemistry: a new 1:1 cocrystal and ternary phase diagram2012In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 12, no 2, p. 869-875Article in journal (Refereed)
    Abstract [en]

    A novel 1:1 cocrystal between p-toluenesulfonamide and triphenylphosphine oxide has been prepared and structurally characterized. This 1:1 cocrystal was observed to form during solid state grinding experiments, with subsequent formation of a known 3:2 cocrystal in the presence of excess sulfonamide. Both cocrystals are stable in the solid state. The ternary phase diagram for the two coformers was constructed in two different solvents: acetonitrile and dichloromethane. Examination of these diagrams clarified solution crystallization of both the newly discovered 1:1 cocrystal and the previously reported 3:2 cocrystal, and identified regions of stability for each cocrystal in each solvent. The choice of solvent was found to have a significant effect on the position of the solid state regions within a cocrystal system.

  • 23.
    Forsberg, Kerstin M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Mohammadi, M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Ghafarnejad Parto, S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Martínez de la Cruz, Joaquin
    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.
    Fredriksson, A.
    LKAB.
    Recovery of REE from an apatite concentrate2014Conference paper (Refereed)
  • 24.
    Forsberg, Kerstin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Mohammadi, M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Ghafarnejad Parto, S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Alemrajabi, Mahmoud
    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.
    Martínez De La Cruz, Joaquin
    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.
    Novel hydrometallurgical methods for recovery and separation of REE2014Conference paper (Refereed)
  • 25.
    Forsberg, Kerstin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Rodríguez Varela, Raquel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Martínez, Joaquin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Kloo, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Processing of a rare earth element concentrate by hollow fibre supported liquid membrane extraction2017Conference paper (Refereed)
  • 26. Gamidi, R. K.
    et al.
    Rasmuson, Åke Christoffer
    University of Limerick.
    Estimation of melting temperature of molecular cocrystals using artificial neural network model2017In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 17, no 1, p. 175-182Article in journal (Refereed)
    Abstract [en]

    quantitative structure-activity relationship model has been constructed by artificial neural networks for estimation of melting temperature (T-m) of molecular cocrystals (CCs). On the basis of a literature, analysis using SciFinder and Cambridge Structural Database softwares, a database has been created of CCs for four active pharmaceutical ingredients, namely, caffeine, theophylline (THP), nicotinamide (NA), and isonicotinamide (INA). In total, of 61 CCs were included: 14-CAF, 9-THP, 29-INA, and 9-NA. A good correlation was obtained with ANNs to quantify the T-m of the CCs with respect to various coformers. The training process was completed with an average relative error of 2.38%, whereas the relative error for the validation set was 2.89%.

  • 27. Granberg, R. A.
    et al.
    Bloch, D. G.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Crystallization of paracetamol in acetone-water mixtures1999In: Journal of Crystal Growth, Vol. 198-199, no pt 2, p. 1287-1293Article in journal (Refereed)
  • 28. Granberg, R. A.
    et al.
    Ducreux, C.
    Gracin, S.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Primary nucleation of paracetamol in acetone-water mixtures2001In: Chemical Engineering Science, Vol. 56, no 7, p. 2305-2313Article in journal (Refereed)
  • 29. Granberg, R. A.
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Solubility of paracetamol in binary and ternary mixtures of water + acetone + toluene2000In: Journal of Chemical and Engineering Data, Vol. 45, no 3, p. 478-483Article in journal (Refereed)
  • 30. Granberg, R. A.
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Solubility of paracetamol in pure solvents1999In: Journal of Chemical and Engineering Data, Vol. 44, no 6, p. 1391-1395Article in journal (Refereed)
  • 31. Heffernan, C.
    et al.
    Ukrainczyk, M.
    Gamidi, R. K.
    Hodnett, B. K.
    Rasmuson, Åke Christoffer
    Synthesis and Solid State Pharmaceutical Centre, Department of Chemical and Environmental Science, Bernal Institute, University of Limerick.
    Extraction and Purification of Curcuminoids from Crude Curcumin by a Combination of Crystallization and Chromatography2017In: Organic Process Research & Development, ISSN 1083-6160, E-ISSN 1520-586X, Vol. 21, no 6, p. 821-826Article in journal (Refereed)
    Abstract [en]

    In this work a method is developed for the extraction and purification of the three curcuminoids, curcumin (CUR), demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC), from commercially available crude curcumin. In a previous publication the extraction of pure curcumin by repeated crystallization has been described. The focus of this paper is on the following chromatographic treatment of the mother liquor from the crystallization to obtain pure DMC and BDMC and to increase the yield of pure CUR. In the chromatographic process, a mixture of chloroform and methanol is used as the mobile phase, and silica gel is used as the stationary phase. Each fraction isolated in the chromatographic process was characterized by high-performance liquid chromatography (HPLC) and mass spectrometry (LC-MS) techniques, and the pure CUR, DMC, and BDMC solid phases were fully characterized by powder Xray diffraction (PXRD), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). Stability studies were performed on the purified curcuminoids where the degradation products were observed and analyzed by HPLC/LC-MS. Overall, the combined purification method recovered from the crude: 88.5%, 79.7%, and 68.8% of CUR, DMC, and BDMC, respectively, in highly pure form CUR (100%), DMC (98.6%), and BDMC (98.3%). © 2017 American Chemical Society.

  • 32. Heffernan, C.
    et al.
    Ukrainczyk, M.
    Zeglinski, J.
    Hodnett, B. K.
    Rasmuson, Åke Christoffer
    Synthesis and Solid State Pharmaceutical Centre, Department of Chemical Sciences, Bernal Institute, University of Limerick.
    Influence of Structurally Related Impurities on the Crystal Nucleation of Curcumin2018In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 18, no 8, p. 4715-4723Article in journal (Refereed)
    Abstract [en]

    In this work, the influence of the structurally related impurities, demethoxycurcumin (DMC) and bisde-methoxycurcumin (BDMC) on the primary nucleation of curcumin (CUR) has been investigated in propan-2-ol. The induction time for nucleation was measured at different CUR driving forces and impurity concentrations 0.10 mmol.dm(-3), 0.30 mmol.dm(-3), and 0.60 mmol.dm(-3) and the results are analyzed by the classical nucleation theory (CNT). The nucleation rate for the impure systems was noticeably lower than the nucleation rate of the pure system, and the times of growth to visibility were much longer for the impure systems. The pre-exponential factors are clearly lower for the impure system compared to the pure CUR system, while the increase in the solid-liquid interfacial energy is small. Density functional theory and metadynamic molecular modeling reveal that the 1:1 bonding between CUR and an impurity molecule is stronger than to another CUR molecule, thus suggesting that the developing CUR nucleus has to overcome a certain energy barrier in order to remove the impurity molecules from their surface, which may explain why nucleation of CUR is more difficult in the presence of the structurally related impurities, DMC and BDMC.

  • 33.
    Hjorth, Timothy
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Svärd, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering. Univ Limerick, Dept Chem & Environm Sci, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Castletroy, Ireland..
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering. Univ Limerick, Dept Chem & Environm Sci, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Castletroy, Ireland..
    Rationalising crystal nucleation of organic molecules in solution using artificial neural networks2019In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 21, no 3, p. 449-461Article in journal (Refereed)
    Abstract [en]

    In this study, the method of artificial neural networks (ANNs) is applied to analyse the effect of various solute, solvent, and solution properties on the difficulty of primary nucleation, without bias towards any particular nucleation theory. Sets of ANN models are developed and fitted to data for 36 binary systems of 9 organic solutes in 11 solvents, using Bayesian regularisation without early stopping and 6-fold cross validation. An initial model set with 21 input parameters is developed and analysed. A refined model set with 10 input parameters is then evaluated, with an overall improvement in accuracy. The results indicate partial qualitative consistency between the ANN models and the classical nucleation theory (CNT), with the nucleation difficulty increasing with an increase in mass transport resistance and a reduction in solubility. Notably, some parameters not included in CNT, including solute molecule bond rotational flexibility, the entropy of melting of the solute, and intermolecular interactions, also exhibit explanatory importance and significant qualitative effect relationships. A high entropy of melting and solute bond rotational flexibility increase the nucleation difficulty. Stronger solute-solute or solvent-solvent interactions are correlated with a facilitated nucleation, which is reasonable in the context of desolvation. A dissimilarity between solute and solvent hydrophobicities is connected with an easier nucleation.

  • 34. Hodnett, B. K.
    et al.
    Maguire, A. R.
    Guiry, P. J.
    Rasmuson, Åke Christoffer
    SSPC, United States.
    Glennon, B.
    Crean, A. M.
    The SSPC: Leading the way for next-generation medicines manufacture2015In: European Pharmaceutical Review, ISSN 1360-8606, Vol. 20, no 4, p. 33-37Article in journal (Refereed)
    Abstract [en]

    The Synthesis and Solid State Pharmaceutical Centre (SSPC), a global hub of pharmaceutical process innovation and advanced manufacturing, is funded by Science Foundation Ireland (SFI) and Industry, and represents a unique collaboration between 22 industry partners, nine research performing organisations and 12 international academic collaborators (Figure 1; page 34). It is a €42 million state-industry investment, which supports a globally-leading research team of 38 investigators, 34 post-doctoral researchers and 60 PhD candidates. As the largest research collaboration in Ireland and one of the largest globally within the pharmaceutical area, the SSPC transcends company and academic boundaries (Figure 2; page 34). Its role is to link experienced scientists and engineers in academia and the pharmaceutical industry, to address critical research challenges and to deliver industry-relevant solutions, which result in job growth and retention within the pharmaceutical industry. © 2015 Russell Publishing Limited

  • 35. Holmbäck, X.
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Size and morphology of benzoic acid crystals produced by drowning-out crystallisation1999In: Journal of Crystal Growth, Vol. 198-199, no PART I, p. 780-788Article in journal (Refereed)
  • 36. Hu, Y.
    et al.
    Erxleben, A.
    Hodnett, B. K.
    Li, B.
    McArdle, P.
    Rasmuson, Åke Christoffer
    Materials and Surface Science Institute, Department of Chemical and Environmental Sciences, University of Limerick.
    Ryder, A. G.
    Solid-state transformations of sulfathiazole polymorphs: The effects of milling and humidity2013In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 13, no 8, p. 3404-3413Article in journal (Refereed)
    Abstract [en]

    The effect of milling on the transitions of sulfathiazole polymorphs in the absence and presence of solvent and excipients was monitored by X-ray powder diffraction (XRPD), attenuated total reflectance infrared (ATR-IR), and near-infrared (NIR) spectroscopy. Sulfathiazole forms FII-FV undergo a transformation toward the metastable FI, which involves an intermediate amorphous stage upon milling at ambient temperature. Milling the commercial form (FC) with catalytic amounts of solvent converts it to pure FIV or to mixtures of FI and FIV depending on the solvent used. Pure FIV can be easily prepared from FC by this method. The physical stability of nonmechanically activated pure sulfathiazole forms in the presence of different levels of relative humidity (RH) was also investigated. At low RH, all sulfathiazole forms are kinetically stable, but at RH levels above 70% FII, FC and FIV remain stable, while FI and FV transform to mixtures of FII and FIV without any apparent change in the external form of the crystals. Comilling FC with a range of excipients gave results that depended on the excipient used, and comilling with cellulose gave samples that had an amorphous content that was stable at 10% RH for at least nine months at ambient temperature.

  • 37. Karpinska, J.
    et al.
    Kuhs, M.
    Rasmuson, Åke C.
    Erxleben, A.
    McArdle, P.
    Ethyl N-[2-(4-phenoxyphenoxy)ethyl]-carbamate2012In: Acta Crystallographica Section E: Structure Reports Online, Vol. 68, no 10, p. o2834-o2835Article in journal (Refereed)
    Abstract [en]

    The title compound, C17H19NO4, which is a non-toxic insect growth regulator with the common name fenoxycarb, contains two independent and conformationally different molecules in the asymmetric unit. Although the inter-ring dihedral angles are similar [62.21 (15) and 63.00 (14)°], the side-chain orientations differ. In the crystal, the molecules are linked through N - H···O hydrogen-bonding associations, giving chains which extend along [110], while intra- and inter-molecular aromatic C - H···π interactions give sheet structures parallel to [110].

  • 38. Korkmaz, K.
    et al.
    Forsberg, K. M.
    Alemrajabi, M.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Sustainable hydrometallurgical recovery of valuable elements from spent nickel-metal hydride hev batteries2016Conference paper (Refereed)
    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, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Alemrajabi, Mahmood
    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 C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Recovery of rare earth elements from spent NiMH HEV batteries via selective roasting and water leaching2017Conference paper (Refereed)
  • 40.
    Korkmaz, Kivanc
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Alemrajabi, Mahmood
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Rasmuson, Åke C.
    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.
    Recoveries of Valuable Metals from Spent Nickel Metal Hydride Vehicle Batteries via Sulfation, Selective Roasting, and Water Leaching2018In: Journal of Sustainable Metallurgy, ISSN 2199-3823, Vol. 4, no 3, p. 313-325Article in journal (Refereed)
    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.

  • 41.
    Korkmaz, Kivanc
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Alemrajabi, Mahmood
    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.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Separation of Valuable Elements from NiMH Battery Leach Liquor via Antisolvent Precipitation2020In: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 234, article id 115812Article in journal (Refereed)
    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%.

  • 42.
    Korkmaz, Kivanc
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Alemrajabi, Mahmood
    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.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Sustainable Hydrometallurgical Recovery of Valuable Elements from Spent Nickel-Metal Hydride HEV Batteries2018In: Metals, ISSN 2075-4701, Vol. 8, no 12Article in journal (Refereed)
    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.

  • 43.
    Korkmaz, Kivanc
    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.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Hydrometallurgical process development for recycling of spent NiMH battery systems from the transport sector2016Conference paper (Refereed)
  • 44. Lindberg, M.
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Product concentration profile in strained reacting fluid films1999In: Chemical Engineering Science, Vol. 54, no 4, p. 483-494Article in journal (Refereed)
  • 45. Lindberg, Magnus
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Reaction crystallization in strained fluid films2001In: Chemical Engineering Science, ISSN 0009-2509, Vol. 56, no 10, p. 3257-3273Article in journal (Refereed)
    Abstract [en]

    The detailed conditions during the ultimate stage of micromixing of the reactants in a reaction crystallization process are analysed. A mathematical model is developed to describe mass transfer, chemical reaction, and crystallization of a molecular compound in strained lamellar structures of reactant solutions inside the smallest vortices. The numerical calculation show that the supersaturation varies significantly in space and time, and suggest that significant crystallization may occur inside these vortices in the case of low-soluble and sparingly soluble compounds. At the end of the vortex lifetime, the crystal size distribution is quite dependent on the properties of the system and on the processing conditions. The number of crystals generated correlates strongly tot he maximum supersaturation occurring during the vortex lifetime, and this maximum supersaturation is as a first approximation well described by simplified mass transfer models where crystallization is neglected. Often a significant supersaturation remains at the end of the vortex lifetime and the size of the crystals leaving the vortex is determined by the growth rate rather than by nucleation and mass constraint. The mean size is usually larger than the limiting size for Ostvald ripening in the bulk and the size distribution is quite narrow. The results show that neglect of the detailed conditions in reaction crystallization of a molecular compound may not be justified.

  • 46. Lindberg, Magnus
    et al.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Supersaturation generation at the feed point in reaction crystallization of a molecular compound2000In: Chemical Engineering Science, ISSN 0009-2509, Vol. 55, no 10, p. 1735-1746Article in journal (Refereed)
    Abstract [en]

    The maximum product concentration of a molecular compound at the feed point in reaction crystallization is analysed by modelling. A model describing unsteady mass transfer and chemical reaction in strained, semi-infinite, fluid films is combined with models describing productivity constraints and reactant concentration changes during the course of a process. The maximum product concentration is taken as a first estimate of the maximum supersaturation and is used as a basis to discuss the product crystal size that may be produced. The result suggests that at certain conditions we may find smaller product crystals at decreased reactant concentrations. The maximum concentration varies during the course of a single-feed semibatch process and the highest value is not necessarily found in the beginning. The variation with time, depends on the choice of the reactant to feed, and the results provide an explanation to why the product crystal mean size may depend on the choice of feed reactant. Guidelines are proposed for how to decide on optimum reactant solution concentrations and for how to select the reactant to feed in a semibatch process. In addition it is suggested that larger crystals may be produced if the feed reactant concentration is low early in the process and is allowed to gradually increase with time in a controlled way. The term “programmed feed concentration” is introduced.

  • 47.
    Liu, Jin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Svärd, Michael
    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.
    Influence of agitation and fluid shear on nucleation of m-hydroxybenzoic acid polymorphs2014In: Proceedings of the 19th international symposium on industrial crystallization, Toulouse, France, 53 (2014), 2014, p. 53-Conference paper (Refereed)
  • 48. Lynch, A.
    et al.
    Verma, V.
    Zeglinski, J.
    Bannigan, P.
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering. Synthesis and Solid State Pharmaceutical Centre, Bernal Institute, Department of Chemical Sciences, University of Limerick, Limerick, Ireland.
    Face indexing and shape analysis of salicylamide crystals grown in different solvents2019In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 21, no 16, p. 2648-2659Article in journal (Refereed)
    Abstract [en]

    The effect of solvent on salicylamide's crystal habit was investigated. Crystals grown experimentally in acetone, acetonitrile and methanol matched the attachment energy predicted rectangle plate vacuum habit. However, in ethyl acetate irregular hexagonal plate crystals form. This change in habit was found to be caused by the stunted growth of specific crystal faces during the crystallisation process. Single crystal and powder X-ray diffraction was carried out to rule out the possibility of a new polymorph. Given no new polymorphs were discovered, the changing habit makes face indexing of experimentally grown crystals difficult. A combination of experimental and modelling prediction tools was employed for the face indexing process. The interfacial angle between faces combined with preferred orientation P-XRD was found to be the most accurate and reliable method leading to successful identification of each salicylamide crystal face. The surface chemistry of each face was examined on a molecular level with insights into the possible growth attachment sites being made. It is deduced that ethyl acetate is adsorbed more strongly on the faces, the increased size of which, can explain the shape change.

  • 49.
    Lynch, Aisling
    et al.
    Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Limerick, Ireland..
    Jia, Lijun
    Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Limerick, Ireland..
    Svärd, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Limerick, Ireland.
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Limerick, Ireland..
    Crystal Growth of Salicylamide in Organic Solvents2018In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 18, no 12, p. 7305-7315Article in journal (Refereed)
    Abstract [en]

    Salicylamide was used as a model active pharmaceutical compound to investigate the crystal growth process and its associated kinetics. The impact of organic solvent, supersaturation, and temperature on the crystal growth was studied. The multiparticle crystal growth kinetics were determined using the seeded isothermal desupersaturation method and modeled using several growth rate equations, using different representations of the driving force. The results showed that crystal growth is significantly influenced by experimental conditions. Within the range of experimental conditions, the growth kinetics was affected strongly by the temperature and to a lesser degree by solvent choice. Comparison of the growth order parameter reveals a surface integration controlled growth. Higher than expected activation energies indicate desolvation as a governing process. A comparison of the influence of the solvent on the crystal growth of salicylamide against previously published approximate data at much higher supersaturation shows good agreement, but the influence on the interfacial energy is opposite to that observed for crystal nucleation. In a detailed comparison with crystal growth data of salicylic acid, there is a consistency in the influence of the solvent on the crystal growth of the two compounds. Salicylamide growth kinetics is more strongly affected by increasing temperature than salicylic acid.

  • 50. Maher, A.
    et al.
    Rasmuson, Åke C.
    Croker, D. M.
    Hodnett, B. K.
    Solubility of the metastable polymorph of piracetam (Form II) in a range of solvents2012In: Journal of Chemical and Engineering Data, Vol. 57, no 12, p. 3525-3531Article in journal (Refereed)
    Abstract [en]

    The solid-liquid solubility of the polymorph known as Form II of 2-oxo-1-pyrolidine acetamide (Piracetam) has been determined gravimetrically in different solvents. Form II is the metastable polymorph of piracetam at ambient conditions and has been isolated and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). Monitoring the solution concentration and the polymorphic composition of the solid phase displayed that this metastable form has a sufficient lifetime when in contact with the solvents to allow measurement of its solubility over the temperature range (278 to 323) K. Four solvents are included: ethanol, 2-propanol, acetone, and 1,4-dioxane. The results show that the solubility of Form II increases with increasing solvent polarity and solvent acidity. Form II has a slightly higher solubility than the stable Form III in all solvents at all temperatures, but the solubility difference is very small. Since Form II is known to transform to Form I below its melting point, a set of regression equations which can be used to extrapolate solubility data to the melting point of Form II were applied to the collected data.

123 1 - 50 of 103
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf