Chuanyong Yan, Ying Zhang, Li Feng
This study investigated the removal of naproxen (NAP) and diclofenac (DIC) from aqueous solutions using an Fe3O4/ZnO/GO magnetic composite. The effects of solution pH, ultrasonic irradiation time, FZG composite amount, and initial drug concentration were studied in a batch system using a Box-Behnken design to evaluate adsorption performance. Analysis of variance (ANOVA) results confirmed the high validity of the proposed model (R² > 0.99). Under optimal conditions (a solution pH rate of 6, an ultrasonic irradiation time of 20 min, an FZG composite amount of 0.023 g, and an initial drug concentration of 35 mg L⁻¹), the removal efficiencies for NAP and DIC reached 94.85% and 96.60%, respectively. The adsorbent's reusability was assessed over five consecutive adsorption/desorption cycles, displaying no significant decline in performance, indicating good stability and reusability of the nanostructure. Furthermore, regeneration experiments demonstrated that the FZG composite retained more than 70% of its initial efficiency after these consecutive cycles, confirming its stability and practical reusability. The results related to the influence of interfering ions indicated that the most common water ions did not adversely affect the removal process. Finally, the FZG composite was tested on tap water, wastewater, and river water, achieving removal efficiencies of 81.53-97.91%. Our findings revealed that the FZG composite is an efficient, reusable, and practical adsorbent for removing NAP and DIC from real water sources, highlighting its high potential for sustainable water treatment applications.