This work reports a dimethyl ether-driven fractional crystallization process for separating rare earth elements and transition metals. The process has been successfully applied in the treatment of rare earth element-bearing permanent magnet leachates as an atom-efficient, reagent-free separation method. Using ~5 bar pressure, the solvent was dissolved into the aqueous system to displace the contained metal salts as solid precipitates.
View Article and Find Full Text PDFA simple, environmentally benign, and efficient chemical separation of rare earth oxalates (CSEREOX) within two rare earth element (REE) subgroups has been developed. The protocol allows for selective solubilization of water-insoluble oxalates of rare earth elements, and results in efficient REE extraction even at low initial concentrations (<5%) from processed magnet wastes.
View Article and Find Full Text PDFThe "butterfly" molecule [Fe3Y(μ3-O)2(CCl3COO)8(H2O)(THF)3] (in brief {Fe3YO2}) includes three Fe3+ ions which build a robust Fe3 cluster with a strong intracluster antiferromagnetic exchange and a total spin S = 5/2. It represents the starting magnetic system to study further interactions with magnetic rare earths when Y is replaced with lanthanides. We present heat capacity and equilibrium susceptibility measurements below 2 K, which show that each cluster has a sizeable magnetic anisotropy pointing to the existence of intercluster interactions.
View Article and Find Full Text PDFCytotoxicity against cancer and normal cells, inhibition of ectonucleotidase, and redox properties of a new group of imidazole-based organic salts and ionic liquids were studied. The tetrachloroferrate salt of a 1-methylimidazole derivative of salicylic aldehyde had most prominent inhibitory activity against ectonucleotidase as well as a higher cytotoxicity against HeLa cells and lower cytotoxicity against BHK-21 cells than the reference compound carboplatin. The studied compounds exhibited a moderate level of antioxidant activity with better results for the salicylic aldehyde derivatives than for spiropyrans.
View Article and Find Full Text PDFActa Crystallogr C Struct Chem
June 2018
A microcrystalline carboxyl-functionalized imidazolium chloride, namely 1-carboxymethyl-3-ethylimidazolium chloride, CHNO·Cl, has been synthesized and characterized by elemental analysis, attenuated total reflectance Fourier transform IR spectroscopy (ATR-FT-IR), single-crystal X-ray diffraction, thermal analysis (TGA/DSC), and photoluminescence spectroscopy. In the crystal structure, cations and anions are linked by C-H..
View Article and Find Full Text PDFWe present the synthesis, structure, magnetic properties, as well as the Mössbauer and electron paramagnetic resonance studies of a ring-shaped [FeLn(Htea)(μ-N)(N)(piv)] (Ln = Y 1, Gd 2, Tb 3, Dy 4, Ho 5, Er, 6) coordination cluster. The Dy, Tb, and Ho analogues show blocking of the magnetization at low temperatures without applied fields. The anisotropy of the 3d ion and the exchange interaction between 3d and 4f ions in FeLn complexes are unambiguously determined by high-field/high-frequency electron paramagnetic resonance measurements at low temperature.
View Article and Find Full Text PDFIn the recently established field of 3d/4f coordination cluster (CC) chemistry several burning questions still need to be addressed. It is clear that combining 3d and 4f metal ions within a coordination cluster core has the potential to lead to electronic structures that will be very difficult to describe but can also be extremely interesting. Furthermore, understanding why certain core topologies seem to be favored is difficult to predict.
View Article and Find Full Text PDFConversion of nitriles under mild conditions leads to a new class of primary amines, including room temperature ionic liquids, acting as efficient anticancer agents.
View Article and Find Full Text PDFDysprosium based ionic liquids displaying slow relaxation of magnetization at low temperatures are reported.
View Article and Find Full Text PDFThe synthesis and magnetostructural properties of a new low-dimensional magnetic system based on α-furoate ligands, {[Dy(α-C4H3OCOO)(μ-(α-C4H3OCOO))2(H2O)3]}n, abbreviated {Dy(α-fur)3}n, are reported. X-ray diffraction experiments results evidence the presence of two different Dy coordination environment types differing only in the position of one of the furoate ligands. The crystallographic structure is formed by polymeric chains along the c-axis, each composed of just one Dy type, coupled within the bc-plane with chains of the same Dy type.
View Article and Find Full Text PDFA new class of task-specific ionic liquids (ILs) which contain septuply positively charged {Fe(3)(III)O(RCOO)(6)L(3)}(7+) triangles has been synthesized and structurally characterized. Such metal-containing ILs can be repeatedly used as alternative catalysts in the synthesis of 2-pyrrolo-3'-yloxindole or the condensation of indoles with various aldehydes.
View Article and Find Full Text PDFA nonanuclear {Fe(6)Dy(3)} coordination cluster displaying SMM behaviour in which an unprecedented chemical transformation provides structural information for the existence of 1,1,2,2-tetrahydroxyethane is reported.
View Article and Find Full Text PDFA new family of hexanuclear ferric-lanthanide [Fe(III)(4)Ln(III)(2)(Htea)(4)(Piv)(6)(N(3))(4)] clusters, where Ln(III) = Er(1) and Lu(2) is reported. Variable temperature solid-state magnetic susceptibility studies of 1 and 2 reveal the presence of ferromagnetic (1) or competing anti- and ferromagnetic exchange interactions (2) between the constituent Fe(III) ions.
View Article and Find Full Text PDFIn this paper we report a comparative study of different procedures for the inter-matrix synthesis (IMS) of monometallic Pd-Polymer-Stabilized Metal NanoParticles (PSMNPs) in sulfonated polyetherether ketone (SPEEK) as stabilizing polymeric matrix. The IMS technique consists in consecutive metal loading-reduction cycles and can be realized by using two different versions: (i) in situ and (ii) ex situ. For in situ IMS the bare polymeric material is first deposited onto the electrode surface followed by metal loading and reduction.
View Article and Find Full Text PDFOne of the routes to overcome the high instability of metal nanoparticles (MNPs) lies in the use of polymeric materials for their synthesis and stabilization. Besides, one of the most serious concerns associated with the growing production and use of MNPs is the possibility of their uncontrollable escape into the medium under treatment and the environment. A possible solution to this problem could be the synthesis of ferromagnetic MNPs with desired functionality, that might not only prevent their escape by using simple magnetic traps but also allow their recovery and reuse.
View Article and Find Full Text PDFNew hetero(micro(3)-oxo)trinuclear iron(III) furoates with the general formulas [Fe(2)MO(alpha-Fur)(6)(L)(H(2)O)(2)], where L = THF (1-3), DMF (4-5), M = Mn(2+) (1, 4), Co(2+) (2, 5), Ni(2+) (3, 6) and [Fe(2)MO(alpha-Fur)(6)(3Cl-Py)(3)], where M = Mn(2+) (7), Co(2+) (8), Ni(2+) (9); have been synthesised and investigated by Mössbauer and IR spectroscopies. The X-ray crystal structure has been determined for the 4 and 8 complexes, indicating that they are related to the monoclinic crystal system (P2(1)/n) and have a structure typical of mu(3)-O-bridged trinuclear iron (III) compounds. The (57)Fe Mössbauer spectra of microcrystalline samples of the compounds indicate the presence of high-spin iron (III) (S = 5/2) with a near symmetrical environments.
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