Comparative study between CeO2/Zno and CeO2/SiO2 nanocomposites for (Cr6+) heavy metal removal

In the present work, nanocomposites of CeO2/ZnO and CeO2/SiO2 were prepared to be used as adsorbing materials for the Cr (VI) heavy metal from water. According to the non-toxic and low-cost properties of zinc oxide and silica, they have been prepared as a nanocomposite with anti-oxidant cerium oxide. The prepared CeO2/SiO2 nanocomposite showed larger removal efficiency for Cr (VI) from aqueous solution of (55%) at optimum conditions of pH = 7 after 100 min. The adsorption kinetics for Cr (VI) on surface of CeO2/Zno and CeO2/SiO2 were well fitted with pseudo-second-order kinetic model. The adsorption mechanism follows monolayer Langmuir isotherm model. The prepared samples were investigated and characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-spectroscopy, field emission scanning electron microscopy (FESEM) and N2 adsorption–desorption isotherm (BET) isotherm. The efficiency of the prepared samples for removing of Cr (VI) from aqueous solution was investigated in different experimental conditions (different PH and contact time).