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Information × Registration Number 0302U005211, 0100U003273 , R & D reports Title Quantitative characteristics of complexation processes in heterogeneous and microheterogeneous media popup.stage_title Кількісні термодинамічні та кінетичні характеристики іонної сорбції на поверхні хімічно модифікованих кремнеземів Head Loginova L.P., Registration Date 22-04-2002 Organization Kharkov National University named after V.N.Karazin popup.description2 The objects to study were silicas chemically modified with aminogroups. The purpose of research was to investigate the protolytic and complexing properties of aminosilicas, to characterize the kinetics of ion sorption; to detect the influence of ionic strength on stability constants of bonded complexes; to calculate the thermodynamic constants of protonization and complexation. Methods of research were potentiometry, diffuse reflection spectroscopy, quantitative physicochamical analysis. The stoichiometric compositions, stability constants and spectral characteristics of Co(II), Ni(II), Zn(II) complexes with n-propylamine and ethylenedimanine grafted on silica surface were determined. The applicability of the model of sorption from semiinfinite solution for the quantitative description of kinetics of sorption was shown. It was found the chemisorption to have the two-stage nature. The ion sorption is of the endothermic nature and is accompanied with the increase of entropy. On the basis of the Pitzer'smethod the model was proposed which permits to describe dependence of the stability constants on the ionic strength of the ionic strength of solutions. The obtained information can be used to optimize the conditions of usage the complexing silicas. Product Description popup.authors popup.nrat_date 2020-04-02 Close