Crystal structure of EuLnAgS<Subscript>3</Subscript> (Ln = Gd and Ho) compounds

The crystal structures of the first prepared EuLnAgS₃ (Ln = Gd and Ho) compounds, which have two polymorphs, were determined by X-ray powder diffraction. α-EuLnAgS₃ phases are isostructural to BaErAgS₃ (monoclinic crystal system, space group C2/m): a = 17.3168(10) Å, b = 3.9683(2) Å, c = 8.3174(4) Å, β = 103.94° (EuGdCuS₃); a = 17.1729(12) Å, b = 3.9367(3) Å, c = 8.2905(6) Å, β = 103.9° (EuHoCuS₃). β-EuLnAgS₃ phases belong to the AgBiS₂ structure type (cubic crystal system, space group Fm-3m): a = 5.739(2) Å (EuGdCuS₃) and a = 5.678 Å (EuHoCuS₃). In the α-EuLnAgS₃ crystal structure, LnS₆ octahedra and AgS₅ trigonal bipyramids share edges to form a three-dimensional (3D) structure with channels accommodating Eu²⁺ ions. A decrease in Ln³⁺ ionic radius gives rise to the crystal-chemical contraction of the 3D structure.     

Dynamic of Exchange Sorption of Transition Metal Ions on Phosphate Cationite KFP-12

The dynamics of ion-exchange sorption of double-charged metal ions on a phosphate cationite KFP-12 was studied. Theoretical calculations of stationary fronts were carried out, the motion velocity of the stationary fronts was calculated, and the rate constant of sorption was evaluated.     

Sorption of M(III) with KFP-12 Phosphonic Cation Exchanger from Chloride Solutions

Sorption by KFP-12 phosphonic anion exchanger of ions of triply charged metals, such as indium, gallium, yttrium, and iron, from chloride solutions was studied. The nature of bonding between sorbed cations and functional groups of the cation exchanger and the mechanism of the ion exchange reaction were elucidated.     

Sorption Kinetics of Ba2+, Cu2+, and Y3+ on KRF-10p Complexing Cation Exchanger

The ion-exchange sorption kinetics of barium, copper, and yttrium on KRF-10p cation exchanger from BaCl₂, CuCl₂, and Y(NO₃)₃ aqueous solutions was studied. The ionic diffusion coefficients were determined as a function of temperature and concentration.