A novel one-step hydrothermal method to prepare CoFe2O4/graphene-like carbons magnetic separable adsorbent

Abstract In this study, a novel one-step hydrothermal method was developed and composite material of CoFe2O4/graphene-like carbons (LGC) was successfully prepared from pomelo peels (PP), Fe(NO3)3·9H2O and Co(NO3)2·6H2O. The characterizing results demonstrate that during the hydrothermal process, (Fe3+ + Co2+) ions adsorbed on the active surface of PP and PP catalyze/prompt the conversions of PP to LGC and (Fe3+ + Co2+) to CoFe2O4, respectively, to produce the composite CoFe2O4/LGC. And CoFe2O4/LGC is nanosized and made of multilayer nanosheets. Its improved adsorptive property for methylene blue (MB) in water is ascribed to the conversion of PP to LGC and exfoliation of PP sheets to nanosheets. Additionally, the composite can be easily and rapidly separated under an external magnetic field and repeatedly used. MB adsorption on CoFe2O4/LGC follows pseudo-second-order kinetics model and Langmuir isotherm models. The synthesis is of simpleness, speediness, low cost, and green non-pollution. CoFe2O4/LGC is an ideal adsorbent candidate.