Studies of malachite green adsorption on covalently functionalized Fe3O4@SiO2-graphene oxides core-shell magnetic microspheres

This paper presents the synthesis of a novel core-shell covalently functionalized Fe3O4 coated SiO2 decorated graphene oxides (Fe3O4@SiO2-GO) adsorbent. The prepared Fe3O4@SiO2-GO was characterized by fourier transform infrared spectrum, X-ray diffraction(XRD), X-ray photoelectroni >> spectroscopy i >> (XPS), and magnetic measurements. And the adsorption properties of the Fe3O4@SiO2-GO toward malachite green were systematically investigated. Various factors possibly affecting the adsorption behavior (initial concentration, contact time, and adsorbent dosage) were also studied in detail. The adsorption capacity (q(m)) of Fe3O4@SiO2-GO for malachite green was found to be 265.87 mg/g with best fit to Langmuir isotherm (R (2) = 0.968), and the adsorption mechanism follows the pseudo-second-order model (R (2) = 0.981). The results indicate that the Fe3O4@SiO2-GO adsorbent, which is easily separated via an external magnetic field, is a potential low-cost effective material for malachite green removal from contaminated water. [GRAPHICS] .