Carbon Nanostructures from Tailings: Synthesis, Characterization and Application in Dye Adsorption

Sectors such as iron mining and the textile industry are of great importance to the economy, but their activities may be related to significant environmental problems, such as the generation of tailings and contaminants in the water, respectively. This work aimed the synthesis of carbon nanostructures by the CVD process, at 900 o C, using methane as carbon source, using two iron ore tailings for later application in the removal of dyes. The characterization of the materials indicated that the pure tailings had iron oxide phases that were transformed into α -Fe and γ -Fe after the CVD process. TG indicated 38.7 and 66.0% of carbon for RA CVD 900 and RL CVD 900, respectively, and Raman indicated the formation of graphitic and well-organized nanostructures. The adsorption results showed that all materials were able to adsorb methylene blue and carmine indigo dyes in aqueous solution, with removal rates of 85 and 53%, with RA CVD 900 being the best material for adsorption.