改性壳聚糖/纳米TiO2微球的制备及其对磷酸盐的吸附研究OA

Excessive phosphate can lead to eutrophication of water bodies.In this study,chitosan is used as the raw material to introduce quaternary ammonium cations onto the amino groups of chitosan,and nano-TiO2 is loaded to prepare Microsphere Titanium dioxide Hydroxypropyltrimethylammonium Chloride Chitosan(MTHAC)via a gel-embedding method.The adsorption performance of MTHAC for phosphate in water is investigated.The microspheres are characterized by FTIR,XRD,and Zeta.The adsorption conditions are optimized using response surface methodology,and the adsorption kinetics and isotherm models are fitted to study the adsorption mechanism.The results indicate that the MTHAC surface exhibits a granular structure,with TiO ₂ uniformly distributed across it,and abundant amino active sites between particles.The MTHAC maintains a positive surface charge within a pH range of 2-8.Under optimized conditions(pH 3,initial phosphate concentration of 50.0 mg·L-1,and adsorption time of 20 h),the maximum adsorption capacity of the composite microspheres reaches 48.7 mg·g-1 with a removal efficiency of 97.3%.The adsorption process follows the pseudo-second-order kinetic model and the Langmuir isotherm model,revealing a monolayer adsorption mechanism dominated by ligand exchange and electrostatic interactions.MTHAC shows favorable recyclable adsorption capacity for phosphate and exhibits significant bacteriostatic activity against Escherichia coli and Staphylococcus aureus.It holds promising potential as a dual-functional phosphorus-removing material integrating bacteriostatic and adsorption properties for application in wastewater treatment.