Elimination performance of methylene blue, methyl violet, and Nile blue from aqueous media using AC/CoFe2O4 as a recyclable magnetic composite

In this study, we have demonstrated a facile one-step solvothermal method for the synthesis of the graphene nanosheet (GNS)/magnetite (Fe(3)O(4)) composite. During the solvothermal treatment, in situ conversion of FeCl(3) to Fe(3)O(4) and simultaneous reduction of graphene oxide (GO) into graphene in ethylene glycol solution were achieved. Electron microscopy study suggests the Fe(3)O(4) spheres with a size of about 200 nm are uniformly distributed and firmly anchored on the wrinkled graphene layers with a high density. The resulting GNS/Fe(3)O(4) composite shows extraordinary adsorption capacity and fast adsorption rates for removal of organic dye, methylene blue (MB), in water. The adsorption kinetics, isotherms and thermodynamics were investigated in detail to reveal that the kinetics and equilibrium adsorptions are well-described by pseudo-second-order kinetic and Langmuir isotherm model, respectively. The thermodynamic parameters reveal that the adsorption process is spontaneous and endothermic in nature. This study shows that the as-prepared GNS/Fe(3)O(4) composite could be utilized as an efficient, magnetically separable adsorbent for the environmental cleanup. Copyright © 2011 Elsevier B.V. All rights reserved. Show more

The potential of garlic peel (GP), agricultural waste, to remove methylene blue (MB) from aqueous solution was evaluated in a batch process. Experiments were carried out as function of contact time, initial concentration (25-200mg/L), pH (4-12) and temperature (303, 313 and 323 K). Adsorption isotherms were modeled with the Langmuir, Freundlich, and Temkin isotherms. The data fitted well with the Freundlich isotherm. The maximum monolayer adsorption capacities were found to be 82.64, 123.45, and 142.86 mg/g at 303, 313, and 323 K, respectively. The kinetic data were analyzed using pseudo-first-order and pseudo-second-order models. The results indicated that the garlic peel could be an alternative for more costly adsorbents used for dye removal. Show more