Effective removal of Ce(III) and Pb(II) by new hybrid nano-material: HnPMo12O40@Fe(III)xSn(II)ySn(IV)1−x−y

Recently, hybrid materials have been very promising in the adsorption/separation of various metal ions due to their unique characteristics. Two important factors are regarded as strategies to synthesize a new material with greatly improved adsorption properties: nanoscale synthesis and hybridization. The novel hybrid inorganic materials HnPMo12O40@Fe(III)xSn(II)ySn(IV)1−x−y were synthesized using the metal ions (Sn(II), Sn(IV), Fe(III)) and heteropolyacid (H3PMo12O40) as precursors by facile chemical method. X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogramimetric analysis (TGA), as well as transmission electron microscopy (TEM), were employed to characterize the product's structural and morphology features. The size of the product estimated from TEM images is significantly smaller than 20 nm. A series of adsorption tests were conducted to analyze the sorption capacity of hybrid for the Pb(II) and Ce(III) ions. The adsorption capacities of 240 mg g−1 and 130 mg g−1 were observed for Pb(II) and cerium(III), respectively. The kinetics of both metal ions was experimentally studied and the obtained rate data were analyzed using simple kinetic models. The results revealed that the pseudo second-order sorption mechanism is predominant and the overall rate constant of each sorption process appears to be controlled by chemical sorption process. The thermodynamic studies show that the sorption of each ion is an endothermic process and spontaneous in nature and increasing temperature improves adsorption performance. The results show that the new nano-hybrid is a promising material for adsorption of Pb(II) and Ce(III).