Investigation of two new low-cost adsorbents functionalized with magnetic nanoparticles for the efficient removal of triclosan and a synthetic mixture.

Abstract

Triclosan (TCS) is widely used in the production of antibacterial products, being often found in wastewater. Therefore, this study developed new materials via soybean hulls (SBHF) and açaí seeds (AÇSF) functionalization with iron oxide nanoparticles to be applied in the TCS adsorption. The characterization confirmed the functionalization of the materials. The adsorption results indicated that the equilibrium of the process occurred after 480 and 960min for SBHF and AÇSF, respectively. The maximum adsorptive capacity values were 158.35 and 155.09mgg-1 for SBHF and AÇSF, respectively, at 318K. The kinetic and isothermal data better fitted to the pseudo-second-order and Langmuir models. Thermodynamics indicated that the processes had an endothermic, spontaneous, and reversible character. The main adsorption mechanisms were H-bond and π-interactions. The pH and ionic strength studies indicated that the adsorption efficiency has not been reduced pronouncedly. The biosorbents reuse was effective for five cycles. In the synthetic mixture, the removal rate was satisfactory (92.53% and 57.02%, respectively for SBHF and AÇSF). These results demonstrate the biosorbents high potential for large-scale application.