Surface ion-imprinted silica clay for adsorption of chromium(III) ions from aqueous with high selectivity

A novel adsorbent ion-imprinted polymer–silica clay (IIP@SC) was prepared via surface ion imprinting technology by using silica clay (SC) as the support matrix and methacrylic acid as the ionic imprinting monomer. The adsorbent was characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray diffrac-tion. The prepared IIP@SC was applied for recovery of Cr(III) ions from aqueous solution. The selectivity properties of IIP@SC are evaluated. The results showed that the maximum adsorption capacity reached 157.98 mg/g in 30 min when the initial concentration of metal ions was 100 mg/L at pH 6.0. Adsorption kinetic and adsorption equilibrium studies demonstrated that the experimental data fitted well with the pseudo-second-order model and the Langmuir isotherm model. Competitive adsorption study showed that the prepared IIP@SC exhibits an efficient selectivity for Cr(III) ions.The prepared IIP@SC adsorbent can be a promising adsorbents for Cr(III) recovery from aqueous solutions with high selectivity.