High-density carboxylated magnetic "gluttonous snake" (HDCMGS): A rapid, efficient, and recyclable adsorbent with...

In this work, a high-density carboxylated magnetic "gluttonous snake" (HDCMGS) was developed via UV curing and magnetic assembly for the removal of methylene blue (MB). The structural evolution of HDCMGS during the magnetic‑assembly process was investigated using SEM. The physicochemical properties of HDCMGS were systematically investigated via FTIR, BET, VSM, and TGA. The effects of pH, HDCMGS dosage, and contact time on MB adsorption were then investigated. HDCMGS exhibited ultra-fast MB adsorption kinetics (87% removal within 10 s, 90%-97% removal within 1 min). Ethanol served as an effective eluent for desorbing MB from MB‑loaded HDCMGS. After 15 adsorption-desorption cycles, the MB removal efficiency of HDCMGS remained above 95% of its initial value. Furthermore, the maximum adsorption capacity of HDCMGS for MB was 434.78 mg⋅g^-1. The MB adsorption process onto HDCMGS was best described by the pseudo‑second‑order kinetic and Freundlich isotherm models. Thermodynamic analysis revealed that the adsorption process was physical, exothermic, and spontaneous. Finally, density functional theory (DFT) calculations revealed that MB adsorption onto HDCMGS was dominated by electrostatic attraction and hydrogen‑bonding interactions. Overall, this work suggests HDCMGS is a promising high‑performance adsorbent for wastewater remediation.