Photocatalytic Inactivation of Different Bacteria and Bacteriophages in Drinking Water at Different TiO2 Concentration With or Without Exposure to O2
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R. Armon
Abstract
During the last decade the use of titanium dioxide has been the focus of water purification studies for photocatalytic degradation of organic compounds. However, the possible use of this technology for water disinfection has been essentially unexplored. In our study U.V. black light (365 nm) at 5.5 mW cm-2 irradiation intensity was used on different TiO2 concentrations (g/L) in batch reactor. Using this irradiation intensity the most effective inactivation of E. coli CN13 was obtained at 1 g/L suspension of TiO2 (viable numbers reduction of 5 orders of magnitude in 5 min was observed). Under the same experimental conditions, MS2 bacteriophage viable count was reduced by 4 orders of magnitude, also in 5 min. B. fragilis bacteriophages have been well documented to be highly resistant to UV irradiation (245 nm) compared to enteric viruses and other bacteriophages. A B. fragilis bacteriophage isolated from sewage was also tested for inactivation, and the results showed a drop of 2 orders of magnitude in 5 min. Tested for longer periods of irradiation, E. coli CN13 was inactivated completely after 60 min (initial concentration 1O6 CFU/mL), MS2 dropped to 1O2 PFU/mL after 60 min (initial concentration 1O9 PFU/mL) and B. fragilis phage dropped to 0 after 60 min (initial concentration 1O4 PFU/mL). The Deinococcus radiophilus bacterium well known to be highly resistant to ionizing radiation (λ-radiation) was also subjected to TiO2 photo- catalytic inactivation in water. The observed reduction in viable count of Deinococcus radiophilus under similar conditions applied to E. coli CN13, was approximately one order of magnitude. However addition of O2 into the experimental environment increased the inactivation of Deinococcus radiophilus by four orders of magnitude in 60 min (first 30 min no inactivation was observed, but in the next 30 min the viable count dropped by four logs). The TiO2 photocalytic inactivation shows promising results for inactivation of microorganisms in drinking water, though further studies are required to optimize this system according to various engineering aspects.
© 2017 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Masthead
- Contents
- Preface
- Editorial
- Research Articles
- Activity, and Hardness of Supported TiO2 Films on Pyrex and Soda-Lime Glass in Photocatalytic Degradation of Formic Acid for 50 Days
- Endurance Test of TiO2-Based Photocatalytic Oxidation
- Photocatalytic Inactivation of Different Bacteria and Bacteriophages in Drinking Water at Different TiO2 Concentration With or Without Exposure to O2
- Solar Photochemical Detoxification and Disinfection for Water Treatment in Tropical Developing Countries
- Photodegradation of Phenol in Water using Silica-Supported Titania Catalysts
- Photocatalytic Decomposition of Chlorinated Benzaldehydes in Aqueous Solution Using TiO2
- Photocatalytic Reduction and Removal of Uranium From a Uranium- EDTA Solution
- Figures-of-Merit for Advanced Oxidation Technologies: A Comparison of Homogeneous UV/H2O2, Heterogeneous UV/TiO2 and Electron Beam Processes
- Gas-Phase Destruction of VOCs Using TiO2/UV and TiO2/O3/UV
- Mass Transfer Considerations in the Design of Vapor-Phase photocatalytic Reactors
- A Simple Kinetic Model for the Simultaneous Concentration and Intensity Dependencies of TCE Photocatalyzed Destruction
Articles in the same Issue
- Masthead
- Contents
- Preface
- Editorial
- Research Articles
- Activity, and Hardness of Supported TiO2 Films on Pyrex and Soda-Lime Glass in Photocatalytic Degradation of Formic Acid for 50 Days
- Endurance Test of TiO2-Based Photocatalytic Oxidation
- Photocatalytic Inactivation of Different Bacteria and Bacteriophages in Drinking Water at Different TiO2 Concentration With or Without Exposure to O2
- Solar Photochemical Detoxification and Disinfection for Water Treatment in Tropical Developing Countries
- Photodegradation of Phenol in Water using Silica-Supported Titania Catalysts
- Photocatalytic Decomposition of Chlorinated Benzaldehydes in Aqueous Solution Using TiO2
- Photocatalytic Reduction and Removal of Uranium From a Uranium- EDTA Solution
- Figures-of-Merit for Advanced Oxidation Technologies: A Comparison of Homogeneous UV/H2O2, Heterogeneous UV/TiO2 and Electron Beam Processes
- Gas-Phase Destruction of VOCs Using TiO2/UV and TiO2/O3/UV
- Mass Transfer Considerations in the Design of Vapor-Phase photocatalytic Reactors
- A Simple Kinetic Model for the Simultaneous Concentration and Intensity Dependencies of TCE Photocatalyzed Destruction
