Freitas G., Vieira M., Silva M., 2017, Kinetic Adsorption of Copper Ions by the Residue of Alginate Extraction from the Seaweed Sargassum Filipendula, Chemical Engineering Transactions, 57, 655-660.
This study focuses on the removal of Cu2+ ions present in low concentration in aqueous solutions using residue of alginate extraction as bioadsorbent from the brown seaweed Sargassum filipendula. Bioadsorption kinetic experiments were carried out at room temperature (25 °C) and at different initial metal ion concentration (1.0, 1.5 and 2.0 mmol/L). Experimental data were described using pseudo-first-order and pseudo-second-order models. Bioadsorption mechanisms were investigated using intraparticle diffusion and Boyd models. It was observed that an average time of 60 minutes was required to reach equilibrium when the initial copper concentration was 1.0 and 1.5 mmol/L, whereas for the initial concentration of 2.0 mmol/L an average time of 120 minutes was required. Besides that, it was observed that the higher the initial concentration of copper in solution, the greater the adsorbed amount of copper. Pseudo-first-order and pseudo-second-order models fitted adequately the experimental data. Intraparticle diffusion and Boyd models showed that external diffusion is the controlling step.
