Adsorption and degradation of norfloxacin by a novel molecular imprinting magnetic Fenton-like catalyst

In this study, a novel magnetically separable adsorbent, molecular imprinting magnetic γ-Fe2O3/crosslinked chitosan composites (MIPs), were prepared by a microemulsion process. Adsorption and Fenton-like oxidative degradation of a model pharmaceutical pollutant norfloxacin (NOR) by using MIPs were investigated. Various characterization methods were used to study the properties of MIPs, and it is suggested that the hydroxyl groups are the main adsorption sites for NOR. MIPs present better selective adsorption for NOR than its reference antibiotic sulfadiazine. The NOR adsorption data can be well fitted by Langmuir isotherm model and pseudo-second-order kinetic model. The optimum pH range for NOR adsorption is 7–10. In addition, the MIP-catalyzed Fenton-like system (MIPs/H2O2) exhibits remarkably faster removal rate for NOR than the case of γ-Fe2O3/H2O2. The result indicates that MIPs will be a good functional material in decontamination of pharmaceutical wastewaters since MIPs can be magnetically recycled after the treatment.

Molecular imprinting γ-Fe2O3/crosslinked chitosan magnetic composites (MIPs) were prepared. Choosing antibiotic norfloxacin (NOR) as the target pollutant, the MIPs have been examined for their selective adsorption behavior of NOR and catalyzing ability in Fenton-like oxidative degradation of NOR. Compared to its reference antibiotic sulfadiazine, the prepared MIPs exhibit observably selective behavior in NOR adsorption. It is suggested that hydroxyl groups are the main adsorption sites for NOR.Figure optionsDownload as PowerPoint slide