Sorption of U(VI) on Schiff-base functionalized metal–organic frameworks UiO-66-NH2

A metal–organic framework, UiO-66-NH2, was designed, synthesized and characterized in this study. By conducting solvothermal method, Salicylaldehyde (Sal) and 2,4-dihydroxybenzaldehyde (MHBA) were grafted onto UiO-66-NH2 via post-treatment to obtain the functionalized material UiO-66-Sal and UiO-66-MHBA. The three materials above were characterized, and the effects of solid–liquid ratio, pH, ionic strength, and oscillation time on U(VI) adsorption were studied. The relevant experimental results fitted well with pseudo-second-order kinetic equation and thermodynamic adsorption model.