Microsphere Zirconomolybdate Sorbents for Extraction of Lanthanides (III) from Aqueous Solutions

Abstract

Micromesoporous zirconomolybdates with a specific surface area of 200 m 2 /g and pore sizes in the range of 10-40 Å (D max ~15 Å) were synthesized under hydrothermal conditions (150 °С, 72 h).Microsphere composites were prepared by deposition of the zirconomolybdates on a microsphere hollow carrier with a macroporous shell (D pore ~ 2-10µm) resulted from the NH 4 F-HCl-H 2 O etching of a cenosphere narrow fraction (-0,08+0,071 mm) separated from coal fly ash of Reftinskaya power station.The morphological type "cenospheres with a porous shell and a smooth surface" predominates in the fraction.The sorption properties of zirconomolybdates and microsphere composites with different Mo/Zr ratio were studied regarding Nd 3+ cations as a surrogate of trivalent actinides.It was established that the thin-layer mode of zirconomolybdate deposition on the carrier and the increasing of a Mo/Zr ratio in its composition provides the enhanced distribution coefficient (up to 10 4 ml/g) and efficiency of Nd 3+ sorption (up to 85 %).