Preparation and characterisation of activated carbon impregnated with goethite and magnetite for dye removal by the combined action of adsorption and oxidation

In this work, methodologies for the precipitation of goethite (G) and magnetite (M) iron oxides on activated carbon (AC0) were applied to prepare two composites (G/AC and M/AC) to remove the Reactive Black 5 (RB5) dye by adsorption/oxidation processes. SEM and EDS showed that the iron oxides partially covered the surface of the AC0, giving a small decrease in the specific surface areas and total pore volume of composites. The FTIR and XRD results showed the presence of goethite on the surface of the G/AC composite (4.23 mgFeg-1), and a mixture of goethite and magnetite oxides in M/AC (30.77 mgFeg-1). The RB5 dye adsorption and oxidation experiments were carried out in initial pH of 3.0 and 6.0. The composites were effective in removing the RB5 dye in the presence of H2O2, since they were able to combine the adsorptive characteristics of AC with the oxidative capacity of iron oxides.