Simultaneous Adsorption Of Cu??? And Methylene Blue Using MgO/SiO₂ Nanocomposites As Adsorbent

Heavy metals and ionic dyes usually exist at the same time, which is one of the most important and dangerous source for environmental pollution. Due to its avaiability and low-cost, SiO2 had been an excellently natural adsorbent. Oweing to the plasticity, specific morphology was easily formed by MgO under certain conditions.In this thesis,MgO/SiO2 nancomposite adsorbent was synthesized by a facile and effective method and characterized by Scanning electron microscope with energy dispersive X-ray(SEM-EDX), X-ray diffraction(XRD), Zeta potentiometer, BET Surface area measurements and the Fourier infrared spectrometer.Some experiments were conducted to study the effect of MgO /SiO2 nancomposite for MB and Cu(?) adsorption. Batch experiments were carried out under different conditions of initial concentration, contact time and pH value to investigate the adsorption of methylene blue and Cu(?) onto MgO/SiO2.The simultaneous adsorption of MB and Cu(?) onto MgO/SiO2 were examined. Reusability of MgO/SiO2 was also investigated.Experimental results showed that MgO was successfully loaded on the surface of SiO2, which increased the active site due to the spherical morphology with many wrinkles and embossment. The pseudo-second-order kinetic model was well fitted with the adsorption kinetic data. The isothermal adsorption process of MB and Cu(?) was fitted by Langmuir and Freundlich isothermal adsorption model. The maximum adsorption capacity of MB and Cu(?) was 83.72 and 208.70 mg/g respectively, under the condition of 25? and pH 4. In MB and Cu(?) simultaneous adsorption and MB preloading experiments, the results indicated that a competitive relationship between MB and Cu(?) was appeared.