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.