Eco-friendly ferrocene-functionalized chitosan aerogel for efficient dye degradation and phosphate adsorption from wastewater

Developing highly efficient, biodegradable and eco-friendly adsorbents to remove pollutants from wastewater has been a significant and long-term global challenge. Herein, a novel aerogel (Fc-CS) has been developed through the functionalization of glutaraldehyde-crosslinked chitosan with ferrocene groups. Methylene blue (MB) and eutrophication ions (PO43-) have been chosen as model pollutants to evaluate the adsorption efficiency of Fc-CS aerogel. The results demonstrated that Fc-CS aerogel possessed high specific surface area and good thermal stability. Freundlich model fitting revealed that both PO(4)(3-)and MB were adsorbed in a multilayered fashion on the Fc-CS aerogel through complex adsorption mechanisms, and pseudo-second-order kinetic model fitting confirmed the involvement of chemical adsorption. Benefiting from the appending of ferrocene groups, FcCS aerogel not only showed excellent PO(4)(3-)adsorption performance, but also provided a Fenton-like active center to catalyze dyes degradation. According to the Langmuir isothermal model, the maximum adsorption capacity for PO(4)(3-)was approximately 1141 mg.g(- 1), exceeding those of most previously reported bio-based adsorbents. The addition of H2O2 significantly enhanced the MB removal efficiency of Fc-CS aerogel from 8.20% to 92.79% by triggering a Fenton-like reaction. After five cycles, no significant attenuation in removal efficiency was observed for either MB or PO43-, with or without H2O2. This eco-friendly and recyclable biomaterial could be an attractive candidate for removing MB and PO(4)(3-)from aquatic systems. The present work provided a feasible pathway to design and develop highly efficient bio-aerogel for wastewater treatment and environmental remediation.

Automated summary

In this study, a novel aerogel with high adsorption efficiency and good thermal stability was developed for removing methylene blue and eutrophication ions from wastewater. With the addition of ferrocene groups, the aerogel not only showed excellent adsorption performance, but also provided a catalytic ability for dye degradation.