1. Decontamination of water by solar irradiation / Sixto Malato, Manuel I. Maldonado, Pilar Fernandez, Isabel Oller and Inmaculada Polo -- 2. Reduction of pentavalent and trivalent arsenic by TiO2-photocatalysis : an innovative way of arsenic removal / Marta I. Litter, Ivana K. Levy, Natalia Quici, Martin Mizrahi, Gustavo Ruano, Guillermo Zampieri and Felix G. Requejo -- 3. Synthesis, characterization and catalytic evaluation of tungstophosphoric acid immobilized onY zeolite / Candelaria Leal Marchena, Silvina Gomez, Liliana B. Pierella and Luis R. Pizzio -- 4. Kinetic aspects of the photodegradation of phenolic and lactonic biocides under natural and artificial conditions / Juan P. Escalada, Adriana Pajares, Mabel Bregliani, Alicia Biasutti, Susana Criado, Patricia Molina,Walter Massad and Norman A. Garcia -- 5. Fenton-like oxidation of phenol with a Cu-chitosan/Al2O3 catalyst in a recirculating batch reactor / Natalia Inchaurrondo, Josep Font and Patricia Haure -- 6. Degradation of a mixture of glyphosate and 2,4-D in water solution employing the UV/H2O2 process, including toxicity evaluation / Melisa Mariani, Roberto Romero, Alberto Cassano and Cristina Zalazar -- 7. Degradation of perchlorate dissolved in water by a combined application of ion exchange resin and zerovalent iron nanoparticles / Luis Cumbal, Daniel Delgado and Erika Murgueitio -- 8. Eco-friendly approach for Direct Blue 273 removal from an aqueous medium / Pamela Yanina Gonzalez Clar, Gustavo Levin, Maria Victoria Miranda and Viviana Campo Dall' Orto -- 9. Decontamination of commercial chlorpyrifos in water using the UV/H2O2 process / Joana Femia, Melisa Mariani, Alberto Cassano, Cristina Zalazar and Ines Tiscornia -- 10. Abatement of nitrate in drinking water. A comparative study of photocatalytic and conventional catalytic technologies / F. Albana Marchesini, Guadalupe Ortiz de la Plata, Orlando Alfano, M. Alicia Ulla, Eduardo Miro andAlberto Cassano -- 11. Photocatalytic inactivation of airborne microorganisms. Performance of different TiO2 coatings / Silvia Mercedes Zacarias, Maria Lucila Satuf, Maria Celia Vaccari and Orlando Alfano -- 12. Water decontamination by heterogeneous photo-Fenton processes over iron, iron minerals and iron-modified clays / Andrea De Leon, Marta Sergio, Juan Bussi, Guadalupe Ortiz de la Plata, Alberto Cassano and Orlando Alfano -- 13. Modified montmorillonite in photo-Fenton and adsorption processes / Lucas M. Guz, Melisa Olivelli, Rosa M. Torres Sanchez, Gustavo Curutchet and Roberto J. Candal -- 14. Photocatalytic degradation of dichlorvos solution using TiO2-supported ZSM-11 zeolite / Silvina Gomez, Candelaria Leal Marchena, Luis Pizzio and Liliana Pierella -- 15. Water disinfection with UVC and/or chemical inactivation. Mechanistic differences, implications and consequences / Marina Flores, Rodolfo Brandi, Alberto Cassano and Marisol Labas -- 16. Ag/AgCl composite material: synthesis, characterization and application in treating wastewater / Wei-Lin Dai, Quan-Jing Zhu, Jian-Feng Guo and Bo-Wen Ma -- 17. Highly photoactive Er3+-TiO2 system by means of up-conversion and electronic cooperative mechanism / Sergio Obregon and Gerardo Colon -- 18. Stabilized TiO2 nanoparticles on clay minerals for air and water treatment / Elias Stathatos, Dimitrios Papoulis and Dionisios Panagiotaras -- 19. Photodegradation of beta-blockers in water / Virender K. Sharma, Hyunook Kim and Radek Zboril -- 20. Final conclusions / Marta I. Litter, Roberto J. Candal and J. Martin Meichtry.