학술논문

Removal of norfloxacin by combining persulfate with nano zero-valent iron modified by activated carbon and copper nanocomposite
Document Type
Academic Journal
Source
Environmental Engineering Research. 2023-10 28(5):82-99
Subject
Advanced oxidation
Bimetal
Degradation mechanism
Nano zero-valent iron
Norfloxacin
Language
Korean
ISSN
1226-1025
2005-968X
Abstract
Advanced oxidation process (AORs) is an effective method to remove a wide range of organic contaminants. However, an outstanding catalysis is needed to generate more free radicals. In this work, nano zero-valent iron (nZVI) modified with activated carbon and copper (AC-nZVI/Cu) was synthesized by liquid-phase reduction, and used to catalyze persulfate (PS) to remove norfloxacin (NOR). The effect of various factors, such as diverse adsorbents, pH, temperature, PS dosage, adsorbent dosage, and inorganic anions, on NOR removal efficiency were investigated. The results show that 30 ㎎/L NOR can be easily removed by 0.5 g/L AC-nZVI/Cu at 313 K through activating 0.5 mM PS, and the removal efficiency is as high as 96.84%. The electron paramagnetic resonance (EPR) analysis proves that numerous sulfate free radicals (·SO₄⁻) appear at the initial stage of the removal process. Furthermore, the quenching experiments manifested that ·SO₄⁻ was the predominant radical special in acidic conditions, while adsorption of NOR was predominant under alkaline conditions. Importantly, compared with nZVI, AC-nZVI/Cu has excellent long-term stability because of the introduction of activated carbon and copper. The study laid the groundwork for further development of adsorbent and activator based on nZVI.