Facile synthesis of mesoporous Fe-based MOFs loading bismuth with high speed adsorption of iodide from solution

To improve the uptake effect of iodide anions from aqueous solution, mesoporous Fe-based MOFs (Bi@MIL) were prepared by mixing Bi(III) and MIL-101(Fe) in Teflon-lined autoclave using solvothermal synthetic method. The Bi@MIL adsorbents were characterized by IR, XRD, SEM, BET and XPS, indicating the crystal structure of MIL-101(Fe) remained when the addition of Bi(III) species in the synthesis of Bi@MIL was below 5.0%. When the amount of Bi(III) reached 15.0%, mesoporous Fe-based MOFs was obtained. Bi@MIL composites displayed fast adsorption kinetics and the adsorption equilibrium was achieved in 20 min in 200 mg L-1 of iodide anions solution concentration at neutral medium. The pH of solution could affect adsorption of iodide anions and the maximum adsorption capacities occurred at pH 3.