Sorbent concentration effect on the adsorption of Pb(II) on Fe3O4@Mg2Al-EDTA LDH in aqueous solution

The adsorption of Pb(II) onto Fe3O4@Mg2Al-EDTA LDH as a function of Fe3O4@Mg2Al-EDTA LDH concentration was studied, and a sorbent concentration effect (C-s-effect), namely, adsorption isotherm declines as sorbent concentration (C-s) increases, was observed. The experimental data were fitted to the adsorption models including the classic Freundlich model and the surface component activity (SCA) model. The results show that the the Freundlich-SCA equation can adequately describe the C-s-effect observed in the batch adsorption tests. In other words, their intrinsic parameters simulated from the experimental data are independent of C-s value. In this case, the values of parameters obtained at given C-s values can used to predict the adsorption behavior for any C-s values.