Effective removal of Pb(II) and Cu(II) from aqueous solutions using a hybrid composite of fuller's earth, aluminum silicate and chitosan

In this study, a highly effective hybrid adsorbent composite based on low-cost fuller’s earth (FE), aluminum silicate (AS) and chitosan (CS) was prepared using a facile method. The prepared composite was applied to adsorb lead (Pb 2+ ) and copper (Cu 2+ ) ions from aqueous solutions. Several analyses such as Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the composite. The adsorption efficiency of the prepared composite was investigated at different operating conditions. Moreover, the adsorption isotherm/kinetic models and adsorption thermodynamics of the composite were examined. The results showed that the pseudo-second-order kinetic model described well with the obtained data and the adsorption equilibrium can be better described by Langmuir isotherm model with maximum adsorption capacities of 305.5 and 284.2 mg/g for Pb 2+ and Cu 2+ , respectively. The obtained data demonstrated that the prepared composite is an efficient and kinetically fast metal ion removal with high adsorption capacity and recovery efficiency. Graphical abstract