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Information × Registration Number 0221U104555, 0120U101971 , R & D reports Title Experimental and theoretical studies of the features governing the synthesis of functional phosphate, hydroxide and oxide materials. popup.stage_title Head Nikolenko Mykola V., Доктор хімічних наук Registration Date 31-03-2021 Organization Ukrainian State University of Chemical Technology popup.description2  The object of research is chemical deposition of high – purity calcium orthophosphates and the processes of extraction of micro-impurities from solutions of precursors of their synthesis. The aim of the work is to establish new knowledge about heterogeneous chemical processes occurring in the synthesis of high – purity calcium orthophosphates. Research methods – kinetic studies, thermodynamic calculations, X-ray phase analysis, mathematical modeling. Regularities and recommendations on optimal conditions for the synthesis of high-purity calcium orthophosphates were developed due to the study of the kinetics of their chemical deposition, which showed that the degree of crystallinity of sediments and their phase composition do not depend on the molar ratio of Ca/P, but are sensitive to the pH of solutions and temperature. These are two key factors that determine the outcome of the phase transformation of metastable phases into less soluble phosphate precipitates. It is proposed to compare the solubility products of calcium orthophosphates with the number of calcium cations in their formulas. A linear correlation was determined between the specific products of the solubility of calcium orthophosphates and their molar Ca/P ratios. A theoretical explanation for such a relationship is proposed for the first time. Thermodynamic and concentration isotherms of solubility of all known calcium orthophosphates are calculated in the range of Ca/P ratios from 0.5 to 1.67. A method for cleaning precursors of phosphate salt synthesis from toxic impurities is developed, which includes conditions for their additional purification from toxic micro-impurities Cu(II), Cd(II), As(III) and Pb(II) by co-precipitation with part of the target product. Scope: C 20.59 Manufacture of chemical products, n. at. and. at. ; M 72.19 Research and experimental development in the field of other natural and technical sciences. Product Description popup.authors Avdiienko Tetiana M. Aksenenko Yevhen V. Vasylenko Kateryna V. Vashkevych Olena Yu. Dolzhykov Serhii S. Dubenko Anastasiia V. Kovalenko Vadym L. Kozyrieva Tetiana I. Labiak Oksana V. Marchenko Raisa T. Myrhorodska Viktoriia D. Myroniak Mariia O. Nikolenko Mykola V. popup.nrat_date 2021-03-31 Close