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Solar-Enhanced Advanced Oxidation Processes for Water Treatment: Simultaneous Removal of Pathogens and Chemical Pollutants.

Tsydenova O, Batoev V, Batoeva A - Int J Environ Res Public Health (2015)

Bottom Line: This is due to competition between chemical substances and pathogens for generated ROS.Other possible negative effects include light screening, competitive photon absorption, adsorption on the catalyst surface (thereby inhibiting its photocatalytic activity), etc.Besides, some matrix components may serve as nutrients for pathogens, thus hindering the disinfection process.

View Article: PubMed Central - PubMed

Affiliation: Baikal Institute of Nature Management, Siberian Branch of the Russian Academy of Sciences, Sakhyanova st. 6, Ulan-Ude City 670047, Russia. tsydenova@yandex.ru.

ABSTRACT
The review explores the feasibility of simultaneous removal of pathogens and chemical pollutants by solar-enhanced advanced oxidation processes (AOPs). The AOPs are based on in-situ generation of reactive oxygen species (ROS), most notably hydroxyl radicals •OH, that are capable of destroying both pollutant molecules and pathogen cells. The review presents evidence of simultaneous removal of pathogens and chemical pollutants by photocatalytic processes, namely TiO2 photocatalysis and photo-Fenton. Complex water matrices with high loads of pathogens and chemical pollutants negatively affect the efficiency of disinfection and pollutant removal. This is due to competition between chemical substances and pathogens for generated ROS. Other possible negative effects include light screening, competitive photon absorption, adsorption on the catalyst surface (thereby inhibiting its photocatalytic activity), etc. Besides, some matrix components may serve as nutrients for pathogens, thus hindering the disinfection process. Each type of water/wastewater would require a tailor-made approach and the variables that were shown to influence the processes-catalyst/oxidant concentrations, incident radiation flux, and pH-need to be adjusted in order to achieve the required degree of pollutant and pathogen removal. Overall, the solar-enhanced AOPs hold promise as an environmentally-friendly way to substitute or supplement conventional water/wastewater treatment, particularly in areas without access to centralized drinking water or sewage/wastewater treatment facilities.

No MeSH data available.


Related in: MedlinePlus

Kinetic constant for E. coli inactivation and initial reaction rate of methylene blue oxidation as a function of TiO2 concentration. Reproduced from [39] with permission from Elsevier.
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ijerph-12-09542-f002: Kinetic constant for E. coli inactivation and initial reaction rate of methylene blue oxidation as a function of TiO2 concentration. Reproduced from [39] with permission from Elsevier.

Mentions: Marugán et al. [39] and Chen et al. [46] have observed a good correlation between TiO2 photocatalytic processes of pollutant oxidation (methylene blue and formaldehyde, respectively) and E. coli inactivation, when analyzing the effect of catalyst concentration and incident radiation flux. The reason for these similarities seems to be due to the common steps of photon absorption and subsequent generation of •OH radicals, which are independent of the type of pollutant. Figure 2 shows kinetic constant for E. coli inactivation and initial reaction rate of methylene blue oxidation as a function of TiO2 concentration. It is clearly seen that for both processes the optimum TiO2 concentration is around 0.1 g/L.


Solar-Enhanced Advanced Oxidation Processes for Water Treatment: Simultaneous Removal of Pathogens and Chemical Pollutants.

Tsydenova O, Batoev V, Batoeva A - Int J Environ Res Public Health (2015)

Kinetic constant for E. coli inactivation and initial reaction rate of methylene blue oxidation as a function of TiO2 concentration. Reproduced from [39] with permission from Elsevier.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4555297&req=5

ijerph-12-09542-f002: Kinetic constant for E. coli inactivation and initial reaction rate of methylene blue oxidation as a function of TiO2 concentration. Reproduced from [39] with permission from Elsevier.
Mentions: Marugán et al. [39] and Chen et al. [46] have observed a good correlation between TiO2 photocatalytic processes of pollutant oxidation (methylene blue and formaldehyde, respectively) and E. coli inactivation, when analyzing the effect of catalyst concentration and incident radiation flux. The reason for these similarities seems to be due to the common steps of photon absorption and subsequent generation of •OH radicals, which are independent of the type of pollutant. Figure 2 shows kinetic constant for E. coli inactivation and initial reaction rate of methylene blue oxidation as a function of TiO2 concentration. It is clearly seen that for both processes the optimum TiO2 concentration is around 0.1 g/L.

Bottom Line: This is due to competition between chemical substances and pathogens for generated ROS.Other possible negative effects include light screening, competitive photon absorption, adsorption on the catalyst surface (thereby inhibiting its photocatalytic activity), etc.Besides, some matrix components may serve as nutrients for pathogens, thus hindering the disinfection process.

View Article: PubMed Central - PubMed

Affiliation: Baikal Institute of Nature Management, Siberian Branch of the Russian Academy of Sciences, Sakhyanova st. 6, Ulan-Ude City 670047, Russia. tsydenova@yandex.ru.

ABSTRACT
The review explores the feasibility of simultaneous removal of pathogens and chemical pollutants by solar-enhanced advanced oxidation processes (AOPs). The AOPs are based on in-situ generation of reactive oxygen species (ROS), most notably hydroxyl radicals •OH, that are capable of destroying both pollutant molecules and pathogen cells. The review presents evidence of simultaneous removal of pathogens and chemical pollutants by photocatalytic processes, namely TiO2 photocatalysis and photo-Fenton. Complex water matrices with high loads of pathogens and chemical pollutants negatively affect the efficiency of disinfection and pollutant removal. This is due to competition between chemical substances and pathogens for generated ROS. Other possible negative effects include light screening, competitive photon absorption, adsorption on the catalyst surface (thereby inhibiting its photocatalytic activity), etc. Besides, some matrix components may serve as nutrients for pathogens, thus hindering the disinfection process. Each type of water/wastewater would require a tailor-made approach and the variables that were shown to influence the processes-catalyst/oxidant concentrations, incident radiation flux, and pH-need to be adjusted in order to achieve the required degree of pollutant and pathogen removal. Overall, the solar-enhanced AOPs hold promise as an environmentally-friendly way to substitute or supplement conventional water/wastewater treatment, particularly in areas without access to centralized drinking water or sewage/wastewater treatment facilities.

No MeSH data available.


Related in: MedlinePlus