Recyclable chitosan adsorbent: Facile functionalization strategy, excellent removal capacity of dyes and adsorption mechanism

• Published in: Chemosphere (Oxford) Vol. 359; p. 142291
• Main Authors: Hui, Yao, Liu, Rukuan, Lan, Jingwen, Sun, Tiantian, Xu, Airong
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.07.2024
• Subjects: Adsorption mechanism; Chitosan; Extraordinary dye adsorption; Polyethyleneimine; Polyethyleneimine; Chitosan; Extraordinary dye adsorption; Adsorption mechanism
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2024.142291

The development of chitosan-based adsorbents with facile preparation, high adsorption performance and reusability for the removal of contaminant dyes remains a persistent challenge. To overcome this challenge, herein, we have developed a novel and extremely facile one-step strategy by which a new high-performance chitosan/polyethyleneimine/polyethylene glycol diglycidyl ether adsorbent (named as CC/PEI/PGDE) has been successfully fabricated via direct functionalization of CC by PEI at ambient temperature followed by subsequent freeze-drying. The Box-Behnken Design was employed to optimize the concentrations of adsorbent components. Attractively, this adsorbent exhibit outstanding adsorption performances to congo red (RED), acid blue-25 (BLUE) and amino black-10B (BLACK) with 2901 mg g−1 (90.9 %), 3434 mg g−1 (90.9 %), and 1438 mg g−1 (90.1 %) of adsorption capacities (removal efficiencies), respectively, and maintains nearly the same adsorption behaviors to original adsorbent even after 6 cycles of adsorption-desorption processes. Meanwhile, three kinetic models, three isothermal models, and the Vant Hoff model are employed to further investigate the adsorption behaviors of RED, BLUE, and BLACK dyes by CC/PEI/PGDE. The results from SEM, EDS, BET, FT-IR, pHZPC and XPS confirm that hydrogen bond interactions and electrostatic attractions play crucial roles in facilitating dyes adsorption by CC/PEI/PGDE. It is expected that this work can bring forward a new perspective for the facile design of high-performance adsorbent for removing anionic dyes from wastewater. [Display omitted] •A new facile one-step strategy for fabricating high-performance chitosan adsorbent.•RSM and BBD were used to determine the optimum ratio of adsorbent component.•2901, 3434 and 1438 mg g−1 of adsorption capacity for three anionic dyes.•Still remain the same adsorption performance to original adsorbent after 6 cycles.