Synthesis of β-Cyclodextrin Polymer Microspheres for Efficient Removal of p-Nitrophenol

In order to create an adsorbent that can efficiently remove p-nitrophenol (PNP) from organic wastewater, this research focused on synthesizing β-cyclodextrin polymer microspheres (β-CDPM). The synthesis utilized epoxy chloropropane (ECH) as a crosslinking agent and β-cyclodextrin (β-CD) as the monomer, employing a conventional reverse-phase emulsion polymerization approach. β-CDPM was characterized using FTIR spectroscopy, SEM, elemental analyzer, and contact angle. The study systematically explored the adsorption performance of β-CDPM for PNP in wastewater across different conditions. Findings revealed that low temperatures and acidic environments favored the adsorption process. Specifically, at 298 K and a pH of 2.0, the adsorption capacity of β-CDPM for PNP attained 50.7 mg·g⁻¹. The adsorption kinetics aligned with the pseudo-second-order kinetic model, whereas the thermodynamic analysis indicated that the adsorption was spontaneous and involved an increase in order. Additionally, the Langmuir isotherm model was determined to better represent the adsorption behavior. As an innovative adsorbent, β-CDPM shows considerable potential for the cost-effective and efficient treatment of organic wastewater.