CHEMICAL ENGINEERING TRANSACTIONS VOL. 29, 2012 A publication of The Italian Association of Chemical Engineering Online at: www.aidic.it/cet Guest Editors: Petar Sabev Varbanov, Hon Loong Lam, Jiří Jaromír Klemeš Copyright © 2012, AIDIC Servizi S.r.l., ISBN 978-88-95608-20-4; ISSN 1974-9791 DOI: 10.3303/CET1229220 Please cite this article as: Derco J., Dudáš J., Šilhárová K., Valičková M., Melicher M. and Luptáková A., (2012), Removal of selected micropollutants by ozonation, Chemical Engineering Transactions, 29, 1315-1320 1315 Removal of Selected Micropollutants by Ozonation Ján Derco* a , Jozef Dudáš a , Katarína Šilhárová b , Mária Valičková a , Michal Melicher a , Anna Luptáková a a Institut of Chemical and Environmental Engineering, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava, Slovak Republic b Water Research Institute, Nábrežie L. Svobodu 5, 812 49 Bratislava, Slovak Republic jan.derco@stuba.sk Micropollutants are natural and manmade substances, such as pharmaceutical and personal care products, pesticides and industrial chemicals, which have been detected in water and in the environment in very low concentrations. Many of them, raise considerable toxicological concerns, are poorly removable by conventional wastewater treatment technologies. To reduce the release of such substances into the aquatic environment two advanced treatment processes based on ozone utilisation were investigated in laboratory scale. Degradation of two types of micropollutants, i.e. selected organochlorine pesticides and oil compounds have been studied. The results of ozonation and O3/(UV show that the highest removal rates were observed during the first 5 minutes of ozonation for all investigated pollutants. Removal efficiencies of chlorinated pesticides were in the range from 70.2 to 90.7 % after 60 minutes of ozonation. Removal efficiencies of about 90 % were observed for all investigated BTX compounds after 40 minutes of ozonation.. 1. Introduction Adoption of the Water Framework Directive (WFD) (EU, 2000) provides a policy tool that enables sustainable protection of water resources. The EC member countries have extended this list by relevant pollutants for individual countries. Thus, in the supplement of the Water Act (Act No. 364, 2004), altogether 59 relevant substances for SR have been identified. Many of the included substances belong to persistent organic pollutants. They are toxic, slowly biologically degradable and accumulative in organisms, in terrestrial and aquatic ecosystems. Environmental Quality Standards Directive (EU, 2008) defines the good chemical status to be achieved by all Member States in 2015 and it gives, together with the WFD (EU, 2000), the legal basis for the monitoring of priority substances in water, sediment and biota. This paper focuses on the use of ozone for the elimination of selected dissolved organic pollutants from water and wastewaters. The first group comprised five selected organochlorine pesticides. Heptachlor (HCH) is an organochlorine compound that was used as an insecticide. The compound was designated as a possible human carcinogen by The International Agency for Research on Cancer (IARC, 2007). Hexachlorobenzene (HCHB) is a fungicide formerly used as a seed treatment, especially on wheat to control the fungal disease bunt. It has been classified by the IARC (2007) as possibly carcinogenic to humans. Hexachlorobutadiene (HCBD) has been classified by the United States Environmental Protection Agency (U.S. EPA, 1991) as a possible human carcinogen. Pentachlorbenzene (PCHB) is very toxic to aquatic organisms, and it decomposes on heating or burning forming toxic, corrosive fumes including hydrogen chloride. Combustion of PCHB can also result in the formation of polychlorinated dibenzodioxins ("dioxins") and polychlorinated dibenzofurans. Lindane (LIN) is the