Synthesis of Fe-ZIF and Adsorption of Zinc and Copper Ions on Its Surface

Abstract

A method for the synthesis of Fe(III)-based zeolite imidazolate framework at various metal to linker ratios was proposed. The resulting material was used as an adsorbent for zinc(II) and copper(II) ions. It was shown that the materials were composed of hexagonal particles and represented a microheterogeneous system with an average particle size of 0.05–0.1 μm. The isotherms of nitrogen adsorption in the pores of Fe-ZIF were measured. By processing of the isotherms, porous structure parameters for the samples were found. The adsorption of Cu2+ and Zn2+ ions from aqueous solutions at 298.15 K was studied and high degrees of metal extraction was demonstrated. The adsorption of copper and zinc ions was spontaneous in all cases. The highest coverages of the surface active sites were 0.96 and 0.71 for copper and zinc, respectively. The adsorption in the bulk of energetically homogeneous porous adsorbent and predominance of micropores in iron(III) 2-ethylimidazolate structure were established.