Photocatalysis disinfection

Fernandez, P., Blanco, J., Sichel, C., and Malato, S. (2005) Water disinfection by solar photocatalysis using compound parabolic collectors. Catalysis Today,... 

The self-cleaning mechanisms of photocatalysis and photosensitization apply also to organic matter included in microorganisms, so it can also lead to selfdisinfection. This is especially expected near a semiconductor (particularly T1O2) and/or iron deposits, which are responsible for solar photogeneration of reactive oxygen species capable of water disinfection [78,79,100,101]. 

The earliest example of the semiconductor photocatalysis application as a method of disinfection was published by Matsunaga et al. (1985). This work reveals that Ti02 particles were effective in the inactivation of bacteria, such as Lactobacillus acidophilus, Saccharomyces cerevisiae, and Escherichia coli. To date more than 200 studies are related with this subject and at least three reviews were dedicated to photocatalytic disinfection (Blake et al. 1999 Srinivasan and Somasundaram 2003 Carp et al. 2004). Some general conclusions on Ti02 disinfection are reported below and the literature will be discussed more specifically throughout the chapter. 

Gumy, D., Rincon, A.G., Hajdu, R. and Pulgarin, C. (2006b) Solar photocatalysis for detoxification and disinfection of water Different types of suspended and fixed Ti02 catalysts study. Solar Energy 80,1376-1381. 

Vidal A, Diaz A1, El Hraiki A, Romero M, Muguruza 1, Senhaji E, Gonzalez J (1999) Solar Photocatalysis for Detoxification and Disinfection of Contaminated Water Pilot Plant Studies, Catal. Today 54 283-290. 

McLoughlin et al. (2004b) have also made a similar comparison between a VTC, a PTC, and a CPC for disinfection of water heavily contaminated with Escherichia coli, both by photocatalysis and by UV irradiation without catalyst. In this case the collectors did not track the sun but were inclined at local latitude with reactor tubes running east-west. It was also found that the CPC had the best performance, followed by the PTC and the VTC, which showed comparable results. It is necessary to point out that the PTC studied was of the nonconcentrating type with a very different configuration with respect to the one used by Bandala et al. (2004). 

Rajeshwar, K. Ibanez, J. G. Electrochemical Aspects of Photocatalysis Application to Detoxification and Disinfection Scenarios, J. Chem. Educ. 1995, 72, 1044— 1049. 

Vidal, A., Diaz, A.I., El Hraiki, A., Romero, M., Muguruza, 1., Senhaji, F., and Gonzalez, J. (1999) Solar photocatalysis for detoxification and disinfection of contaminated water pilot plant studies. Catal. Today, 54, 283—290. 

Finally, the effectiveness of photocatalysis for disinfection has been further assessed. In particular, the optimization of the treatment and the control of bacterial regrowth have been investigated. ... 

Malato S, Femandez-Ibanez P, Maldonado MI, Blanco J, Gemjak W (2009) Decontamination and disinfection of water by solar photocatalysis recent overview and trends. Catal Today 147 1-59... 

Remy SP, Simonet F, Cerda EE, Lazzaroni JC, Atlan D, Guillard C (2011) Photocatalysis and disinfection of water identification of potential bacterial targets. Appl Catal B Environ 104 390-398... 

Photoelectrochemical Disinfection of Air (Ti02), Fig.1 Schematic illustration of applications of photocatalysis... 

In conclusion, we can expect a large number of applications in the photoelectrochemical disinfection of air by using Ti02 photocatalysts because of the expansion to new fields of research and development. In particular, we feel that achieving a healthy and comfortable living environment is becoming an important issue, and Ti02 photocatalysis can fulfill an important role in the disinfection of air. 

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