Background& Objective: Pharmaceuticals, especially antibiotics, are newborn contaminants Due to its cumulative nature, adverse effects and drug resistance; it has created a major concern for environmental control. An example of these antibiotics is metronidazole (MNZ). Therefore, the purpose of this study was to determine the efficiency of removal of MNZ from aqueous solution using the nano/persulfate process (nZVI/PS).
Materials and Methods: This experimental study was conducted on a laboratory scale and in a batched system. The effects of factors such as pH of solution (3-11), reaction time (5-150 min), dose of nanoparticle (0.025-2 g/L), the concentration of persulfate (0.1-3.33 mmol), and the initial concentration of metronidazole (1-120 mg/L) were studied on the removal efficiency. Metronidazole was measured by HPLC device.
Results: The results of this study showed that at the optimal pH 3, the highest removal efficiency of metronidazole was obtained. With a 30 minute contact time and 25 mg/L initial concentration of metronidazole, the removal efficiency was 90.3%. The optimal and economical dose of nZVI was also obtained at 0.5 g/L and persulfate was 1.85 mM.
Conclusion: The results of this study showed the acceptable performance of nano/persulfate process in the removal of metronidazole. And an increase of 62.4%, confirms the good effect of zero valent-iron nanoparticles on persulfate activation.