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

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Yang Xiao
Yang Xiao
Yang Xiao
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Yang Shao at Chinese Academy of Sciences
Yang Shao
Min Luo
Min Luo
Min Luo
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Ling-ling Ma
Ling-ling Ma
Ling-ling Ma
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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.
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Optimized Study and Column Experiments on Treatment
Process of Metronidazole Pharmaceutical Wastewater
by Microelectrolysis and Fenton Oxidation
Yang Xiao &Yang Shao &Min Luo &Ling-ling Ma &
Dian-dou Xu &Ming-hong Wu &Gang Xu
Received: 27 October 2020 /Accepted: 6 April 2021
#The Author(s), under exclusive licence to Springer Nature Switzerland AG 2021
Abstract One of the most important wastewater treat-
ment processes is microelectrolysis, which is extensive-
ly used in the primary treatment of pharmaceutical
wastewater. In this study, microelectrolysis, as a pre-
treatment method for the refractory metronidazole phar-
maceutical wastewater (MPW) of choice, was improved
using the Fenton process and used to remove the chem-
ical oxygen demand (COD) and improve the biochem-
ical 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 demonstrat-
ed 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 improve-
ment. Finally, the breakthrough curves at different flow
rates were measured to prove the feasibility of the com-
bined process under optimal conditions.
Keywords Microelectrolysis .Fenton .Metronidazole .
Plackett–Burman design .Ultraviolet–visible (UV–Vis)
spectroscopy
1Introduction
The consumption of pharmaceuticals for human and
veterinary uses shows an upward trend over the last
decades (Zrncevic, 2016). However, the unnecessary
use and inappropriate disposal of antibiotics have in-
creased the amount of antibiotics residue or their
decomposed products in natural environments (Zhou
et al., 2019). In-depth research on water environmental
deterioration in recent decades has led to an increased
attention to environmental antibiotic pollution (Bu et al.,
2016; Hama, 2019; Hanna et al., 2018). Hazardous
wastewater from the pharmaceutical plants and domes-
tic sewage contains drug residue from human consump-
tion can be discharged through wastewater treatment
systems to receiving rivers near surrounding areas
(Dinda et al., 2020). Recently, a study about environ-
mental pollution says that antimicrobials were found in
every site except the groundwater dominated Thames
source (White et al., 2019). The presence of antibiotics
in the environment can change the structure and activity
of environmental microbiota (Biyela et al., 2004). Fur-
thermore, the worst consequence was the dissemination
of resistance genes among ecosystems (Chen et al.,
2019). In summary, the treatment of pharmaceutical
wastewater is particularly important.
https://doi.org/10.1007/s11270-021-05117-z
Y. Xiao :Y. Shao :M. Luo (*):L.<l. Ma :D.<d. Xu
Beijing Engineering Research Center of Radiographic Techniques
and Equipment, Institute of High Energy Physics, Chinese
Academy of Sciences, Beijing 100049, China
e-mail: minluo@ihep.ac.cn
Y. Xiao :M.<h. Wu :G. Xu (*)
College of Environment and Chemical Engineering, Shanghai
University, Shanghai 200444, China
e-mail: xugang@shu.edu.cn
/ Published online: 22 April 2021
Water Air Soil Pollut (2021) 232: 182
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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