Photo-Fenton and modified photo-Fenton at neutral pH for the treatment of emerging contaminants in wastewater treatment plant effluents: A comparison

AbstractThis work investigated an innovative alternative to improve municipal wastewater treatment plant effluent (MWWTP effluent) quality aiming at the removal of contaminants of emerging concern (caffeine, carbendazim, and losartan potassium), and antibiotic-resistant bacteria (ARB), as well as disinfection (E. coli). Persulfate was used as an alternative oxidant in the solar photo-Fenton process (solar/Fe/S2O82−) due to its greater stability in the presence of matrix components. The efficiency of solar/Fe/S2O82− at neutral pH using intermittent iron additions is unprecedented in the literature. At first, solar/Fe/S2O82− was performed in a solar simulator (30 W m−2) leading to more than 60% removal of CECs, and the intermittent iron addition strategy was proved effective. Then, solar/Fe/S2O82− and solar/Fe/H2O2 were compared in semi-pilot scale in a raceway pond reactor (RPR) and a cost analysis was performed. Solar/Fe/S2O82− showed higher efficiencies of removal of target CECs (55%), E. coli (3 log units), and ARB (3 to 4 log units) within 1.9 kJ L−1 of accumulated irradiation compared to solar/Fe/H2O2 (CECs, 49%; E. coli, 2 log units; ARB, 1 to 3 log units in 2.5 kJ L−1). None of the treatments generated acute toxicity upon Allivibrio fischeri. Lower total cost was obtained using S2O82− (0.6 € m−3) compared to H2O2 (1.2 € m−3). Therefore, the iron intermittent addition aligned to the use of persulfate is suitable for MWWTP effluent quality improvement at neutral pH.

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Inactivation of Enterococcus faecalis in simulated wastewater treatment plant effluent by solar photo-Fenton at initial neutral pH

Catalysis Today ◽

10.1016/j.cattod.2013.03.001 ◽

2013 ◽

Vol 209 ◽

pp. 195-200 ◽

Cited By ~ 31

Author(s):

E. Ortega-Gómez ◽

B. Esteban García ◽

M.M. Ballesteros Martín ◽

P. Fernández Ibáñez ◽

J.A. Sánchez Pérez

Keyword(s):

Wastewater Treatment ◽

Enterococcus Faecalis ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Neutral Ph ◽

Simulated Wastewater ◽

Wastewater Treatment Plant Effluent

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Simultaneous photocatalytic oxidation of pharmaceuticals and inactivation of Escherichia coli in wastewater treatment plant effluents with suspended and immobilised TiO2

Water Science & Technology ◽

10.2166/wst.2012.868 ◽

2012 ◽

Vol 65 (11) ◽

pp. 2016-2023 ◽

Cited By ~ 14

Author(s):

Cristina Pablos ◽

Rafael van Grieken ◽

Javier Marugán ◽

Alejandra Muñoz

Keyword(s):

Escherichia Coli ◽

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Photocatalytic Oxidation ◽

Emerging Contaminants ◽

Fixed Bed ◽

Treatment Plant ◽

Fixed Bed Reactor ◽

Low Concentrations ◽

Chemical Composition Of Water

Simultaneous Escherichia coli inactivation and oxidation of pharmaceuticals in simulated wastewater treatment plant effluents has been investigated using a photocatalytic treatment with TiO2 in suspension and immobilised onto a fixed-bed reactor. Non-photocatalytic reference experiments of dark adsorption and photolysis showed a higher sensitivity of E. coli towards the chemical composition of water in comparison with the concentration of pharmaceuticals that remains unaffected. Moreover, it must be underlined that the presence of pharmaceuticals (including antibiotics) did not seem to affect the bacterial viability at such low concentrations. Concerning photocatalytic experiments, both suspended and immobilised TiO2 were able to simultaneously inactivate and oxidise both kinds of pollutants (bacteria and pharmaceuticals). The fixed-bed reactor showed similar activity to that of the slurry without deactivation after several cycles of reuse. That makes TiO2 photocatalysis a quite interesting technology for the treatment of drinking water supplies or wastewater plant effluents, allowing the removal of emerging contaminants such as pharmaceuticals during the disinfection treatment.

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