<b>Biosorbent of macadamia residue for cationic dye adsorption in aqueous solution

Resumo

This study evaluated the adsorption capacity of the methylene blue dye in macadamia residues, in natura and chemically modified. The waste characterization was performed using SME and spectroscopy in the infrared region, indicating the presence of carboxyl, carbonyl and hydroxyl groups. The equilibrium time for both residues was 240 minutes, following a kinetic described by models of the pseudo second-order and intra-particle diffusion. The maximum adsorption capacity was 117 mg g^-1 to the residue in natura and 184 mg g^-1 for the modified one, and was described by the Freundlich isotherm model. The system demonstrated to be spontaneous and favorable for both studied materials. Thus, these residues are promising for the adsorption of methylene blue dye in effluents.