Extraction of polyoxotantalate by Mg-Fe layered double hydroxides: elucidation of sorption mechanisms.

ABSTRACT: The extraction of Ta(v) as polyoxometallate species (H _x Ta₆O₁₉ ^(8-x)-) using Mg-Fe based Layered Double Hydroxide (LDH) was evaluated using pristine material or after different pre-treatments. Thus, the uptake increased from 100 ± 5 mg g^-1 to 604 ± 30 mg g^-1, for respectively the carbonated LDH and after calcination at 400 °C. The uptake with calcined solid after its reconstruction with Cl^- or NO₃ ^- anions has also been studied. However, the expected exchange mechanism was not found by X-ray Diffraction analysis. On the contrary, an adsorption mechanism of Ta(v) on LDH was consistent with measurements of zeta potential, characterized by very negative values for a wide pH range.

SUBMITTER: Choumane R 

PROVIDER: S-EPMC9043620 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature