Optimized Study and Column Experiments on Treatment Process of Metronidazole Pharmaceutical Wastewater by Microelectrolysis and Fenton Oxidation

One of the most important wastewater treatment processes is microelectrolysis, which is extensively used in the primary treatment of pharmaceutical wastewater. In this study, microelectrolysis, as a pretreatment method for the refractory metronidazole pharmaceutical wastewater (MPW) of choice, was improved using the Fenton process and used to remove the chemical oxygen demand (COD) and improve the biochemical capability of MPW. The results showed that the highest COD removal of 40.8% was obtained in the presence of optimized significant factors and the BI (BI = biochemical oxygen demand over five days/COD) of MPW increased from 0.10 to 0.31. In addition, the ultraviolet-visible (UV-Vis) spectroscopy demonstrated that metronidazole in MPW was effectively removed during the combined processes. All these results showed that microelectrolysis combined with Fenton oxidation for MPW was an effective treatment process to achieve higher COD removal and biodegradability improvement. Finally, the breakthrough curves at different flow rates were measured to prove the feasibility of the combined process under optimal conditions.

Automated summary

The combination of Fenton process with microelectrolysis in treating refractory metronidazole pharmaceutical wastewater showed significant improvement in COD removal and biodegradability enhancement. The results indicated that this combined process was effective in achieving higher treatment efficiency for MPW.