Immobilization of chitosan grafted carboxylic Zr-MOF to porous starch for sulfanilamide adsorption

• Published in: Carbohydrate polymers 2021-02, Vol.253, p.117305-117305, Article 117305
• Main Authors: Jia, Xiangze, Zhang, Bin, Chen, Chun, Fu, Xiong, Huang, Qiang
• Format: Article
• Language: English
• Subjects: Adsorption; Chitosan; Porous starch; Sulfanilamide; UiO-66-COOH
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2020.117305

[Display omitted] •A novel UiO-66-COOH composite with hierarchical porosity was synthesized.•Carboxylic Zr-MOF nanoparticles were immobilized within porous starch.•The accessibility of UiO-66-COOH within the composite was preserved.•The Zr-MOF composite was efficient and reusable for sulfanilamide removal. A novel hierarchical porous starch-chitosan-UiO-66-COOH composite for the treatment of pharmaceutical-bearing sewage was developed. UiO-66-COOH-type carboxylic zirconium metal organic framework (Zr-MOF) was synthesized and immobilized within porous starch through a facile chitosan-adhesive strategy. The porous starch offered a stable macro-porous structural skeleton to accommodate the UiO-66-COOH nanoparticles, and chitosan played the role of an affinity agent to strengthen the decoration effect via electrostatic interaction and hydrogen bonding with carboxylic Zr-MOF particles and porous starch, respectively. The carboxylic Zr-MOF composite not only preserved the intrinsic accessibility of UiO-66-COOH but also maintained unique crystallization and thermal properties. The adsorption of sulfanilamide into the porous starch-chitosan-UiO-66-COOH composite conformed to pseudo-second-order kinetic and Langmuir isothermic models, demonstrating that adsorptions could be considered as homogeneous monolayer chemisorption. The Zr-O group within the carboxylic Zr-MOF composite displayed high affinity for sulfanilamide and possibly played a crucial role in sulfanilamide adsorption.