Abstract
In this study, manganese ferrite-graphene oxide (MFO-GO) nanocomposites were prepared via a co-precipitation reaction of Fe3+ and Mn2+ ions in a GO suspension. The effects of graphene oxide on the physicochemical characteristics, magnetic properties and adsorption activities of the MFO-GO nanocomposites were studied. Methylene blue (MB) and arsenic(v) were used in this study as model water pollutants. With an increase in the GO content in the range of 10 wt% to 50 wt%, the removal efficiency for both MB dye and arsenic(v) ions was improved. Our adsorption data revealed that the adsorption behavior of MB dye showed good agreement with the Langmuir isotherm model and pseudo-second-order equation, whereas the Freundlich isotherm model was more suitable for simulating the adsorption process of arsenic(v) ions on the MFO-GO nanocomposites. In addition, an important role of the GO content in the adsorption mechanisms of both MB dye and arsenic(v) ions was found, in which GO nanosheets play a key role in the mechanisms of electrostatic/ionic interactions, oxygen-containing groups and π–π conjugation in the case of the adsorption of MB dye, whereas the role of the GO content is mainly related to the mechanism of electrostatic/ionic interactions in the case of the adsorption of arsenic(v). Graphene oxide has the functions of increasing the number of active binding sites comprising oxygen-containing functional groups, reducing the agglomeration of MFO nanoparticles, increasing the number of adsorption sites, and improving the electrostatic/ionic interactions between adsorbents and adsorbates in order to enhance the adsorption performance of cationic organic dyes and/or heavy metal anions from aqueous solutions.
Highlights
Water is one of the most important substances on the earth because it is essential for life
MFO nanoparticles were deposited on the surface
The results showed that the saturation magnetization (Ms) of the bare MFO nanoparticles was about 20 emu gÀ1, whereas the Ms values of the manganese ferrite-graphene oxide (MFO-GO) nanocomposite samples decreased with an increase in the GO concentration from 12.2 emu gÀ1 (10% GO content) to 3.2 emu gÀ1 (50% GO content)
Summary
Inorganic arsenic is a typical inorganic pollutant in water and has high toxicity and carcinogenicity. There are various technological methods for water treatment such as screening, ltration, centrifugal separation, sedimentation, coagulation, adsorption, and/or electrolysis Among these techniques, adsorption methods are among the most promising solutions for water decontamination because of their low costs, high efficiency and exibility in operation and the scale of treatment.[5] There have been many intensive studies of the development of various nanomaterial-based adsorbents such as graphene, carbon nanotubes, metal oxide/magnetic nanoparticles, and their composites/hybrids for the removal of pollutants from water.[6,7,8,9] Among existing nanoadsorbents, manganese ferrite-graphene oxide (MFO-GO; MFO 1⁄4 MnFe2O4) nanocomposites[10,11,12] have attracted much interest for the highly efficient removal of both organic dyes, e.g., methylene blue (MB), and heavy metal ions, e.g., arsenic(III), arsenic(V), and lead(II). Kumar et al.[12] showed that hybrids of single-layer graphene oxide with MFO nanoparticles exhibited the best adsorption properties for the efficient removal of lead(II), arsenic(III), and arsenic(V) from contaminated water. Bene cial effects of the GO content on the adsorption mechanisms of magnetically separable GO-MFO adsorbents were proposed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
