[Adsorption Properties and Host-guest Effects of Porous Cyclodextrin Polymers for Dye Molecules in Water]

Cyclodextrin can form host-guest inclusion complexes with a variety of organic pollutants and has unique advantages in removing complex dye molecules from water. In this study, a porous cyclodextrin polymer (P-CDP) was prepared using a rigid crosslinking agent, and the structure of the P-CDP was characterized by FT-IR, XPS, SEM, BET, and other technologies. The P-CDP was studied using isothermal adsorption and kinetic adsorption experiments. The inclusion adsorption performance and host-guest effect of the P-CDP for dye molecules in water were studied using competitive experiments. The characterization results showed that the P-CDP had strong thermal stability. It had a microporous structure with a specific surface area of 108.745 m²·g^-1. The Langmuir model and the pseudo-second-order kinetic model had a higher fitting degree for the adsorption process. The results of the competition experiments showed that the electrostatic effect was stronger than the host-guest effect in the adsorption process. Pollutants whose molecular configurations were highly matched with the cyclodextrin cavity could form inclusion complexes with high molecular stability. Contaminants with strong hydrophobicity were more likely to be encapsulated in the cyclodextrin cavity. After the P-CDP adsorbed the dyes, the removal efficiency after the fifth cycle of elution and regeneration remained above 80%. This study showed that P-CDP has potential application value in the treatment of dye wastewater.