A novel crosslinking strategy on functional cellulose-based aerogel for effective and selective removal of dye

Motivated by sustainable development, the huge pressure of harmful dyes wastewater treatment has highlighted an urgent need to develop more effective biomass adsorbents for selective removal and separation of dyes. Herein, cellulose-based aerogel adsorbent (CPB) is successfully prepared through a novel crosslinking strategy for static and dynamic dye removal, starting with the fabrication of cellulose acetoacetate (CAA) and β-cyclodextrin acetoacetate (β-CDAA) through transesterification process, followed by the crosslinking of polymer chains using polyethyleneimine (PEI) through the formation of dynamic enamine bonds and the freeze-drying treatment of three-dimensional (3D) network structures. A maximum adsorption capacity toward methyl orange (MO) up to 1013.11 mg g−1 is achieved at 25 °C. Besides, the CPB aerogel has abundant surface positive charge, which can be employed to selectively remove anions dyes from ternary mixed systems and has additional antibacterial activity. More importantly, the CPB material based on the dynamic crosslinking strategy can be regulated by adjusting pH, which greatly facilitates the reprocessing and utilization of the adsorbent. The cellulose-based aerogel presented in this work could be an extremely promising material for dye wastewater treatment.