Efficient removal of ciprofloxacin in aqueous solutions by magnetic Se-MOF embedded within a biopolymer (chitosan/alginate): Adsorptive behavior, mechanism study, and optimization using Box-Behnken design.

A novel magnetic selenium-based metal-organic framework (MSe-MOF) incorporated into chitosan/alginate biopolymer hydrogel beads (MSCA) has been developed for the effective adsorption of ciprofloxacin (CIP), a commonly utilized fluoroquinolone antibiotic, from aqueous solutions. The hybrid composite was synthesized through an environmentally friendly fabrication process and widely characterized by several analytical performances, including XRD, SEM, EDX, FT-IR, XPS, and nitrogen adsorption/desorption isotherms. The characterization consequences validated the establishment of a porous architecture through a substantial specific surface area of 420 m2/g, which is conducive to efficiently capturing contaminants. Batch adsorption tests were conducted to assess the effects of pH, adsorbent amount, interaction time, initial CIP concentration, and temperature on the adsorption procedure. The equilibrium adsorption data aligned most closely with the Langmuir isotherm model, exhibiting a 440 mg/g maximum adsorption capacity, while the kinetics adhered to a pseudo-second-order model, signifying chemisorption as the predominant mechanism. Thermodynamic parameters (ΔH° > 0 and ΔS° > 0) indicated that the process is endothermic and driven by entropy. Method of optimization was accomplished utilizing the Box-Behnken design within the framework of Response Surface Methodology (RSM), which affirmed the statistical significance and robustness of the model. Furthermore, the MSCA hydrogel beads exhibited outstanding reusability across multiple cycles with negligible performance degradation. These effects emphasize the potential of MSCA as a sustainable, biodegradable, and operational medium for the elimination of pharmaceutical contaminants from wastewater.