Layered double hydroxides intercalated with EDTA as effective sorbents for U(VI) recovery from wastewater

Abstract

The performance of the synthetic hydrotalcite-like sorbents, initial {[Zn4Al2(OH)12]CO3·nH2O} and heat-treated (Zn4Al2O7) forms and the form intercalated with EDTA and prepared in a nitrogen atmosphere from [Zn4Al2(OH)12]Cl2·nH2O, was evaluated and compared. Increased concentrations of hydrocarbonate and carbonate ions do not noticeably affect the degree of U(VI) recovery from wastewaters with pH 8, which is due to tight binding of U(VI) with EDTA anions in the interlayer space of layered double hydroxides. [Zn4Al2(OH)12]EDTA·nH2O is one of the most effective and cheapest synthetic sorbents for recovering from aqueous media not only cationic but also anionic U(VI) species, which is particularly important. Therefore, the sorbent can be recommended for practical use.