Cubic analcime and analcime-zirconia composite with the Si/Al ratio of 2.04 and 2.16, respectively, was synthesized by hydrothermal treatment of coal fly ash cenospheres (Si/Al ¼ 2.7) at 150 C. The scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), synchronous thermal analysis (STA) methods were used to study the morphology, composition and structure of the products. Two main types of analcime bearing particles were obtained, such as hollow microspheres with attached analcime icositetrahedra of 5 e50 mm in size and individual analcime crystals of a narrow particle size distribution (D m ¼ 41 mm) with incorporated zirconia (4.8 wt% Zr). The high quality of the crystalline fractions allowed an accurate fullprofile PXRD analysis of complete analcime crystal structure and composition including anisotropic displacement parameters of all atoms and H-positions of water molecules.

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The influence of hydrothermal conditions on synthesis of analcime and a composite material ZrO2- analcime as well as zirconomolybdate coverings with ion exchange properties was studied using narrow fractions of aluminosilicate microspheres with a high content of a glass phase (91-95 wt. %). The possibility to synthesize ZrO2-analcime composites of narrow particle size distributions with maximum of about 40 μm and 6 μm under hydrothermal treatment at 150 °С was demonstrated starting from microspheres with Si/Al=2.7 and applying different regimes of a reaction mixture agitation. A microsphere material of a “core-shell” type such as ZrMo2O7(OH)2(H2O)2@(SiO2-Al2O3)glass with the nanostructured covering was prepared. Sorption properties of the materials regarding Nd3+, Sr2+ and Cs+ were studied under equilibrium conditions by means of determination of sorption isotherms and their fitting by the Langmuir model. Sorption parameters were determined including distribution coefficients which reach the values of 104−105 mL/g

Magnetic sorbents were prepared by addition of ferrospheres to zirconia-silica gel followed by thermal treatment at 500 °C. The ferrosphere narrow fraction E -0.063+0.050 mm from fly ash resulted from combustion of Ekibastuz coal was used as a magnetic component. The surface of magnetic composites was additionally functionalized by grafting of – POONa and – NH2 groups. Under equilibrium conditions sorption capacities of the sorbents with respect to Се3+ used as a U4+/Th4+ simulator and Pb2+ were measured by means of determination of sorption isotherms which were fitted by the Langmuir model. It was established that extraction of Се3+ and Pb2+ from aqueous solutions is characterized by distribution coefficients of 104–106 ml/g. Temperature conditions for solid-phase crystallization of the sorbents resulting in polyphase systems with the content of zircon phase of 50 wt. % were found