Removal of 2,4-dimethylphenol pollutant in water by ozonation catalyzed by SOD, LTA, FAU-X zeolites particles obtained by pseudomorphic transformation (binderless) Jullian Vittenet a,b , Jeremy Rodriguez a , Eddy Petit b , Didier Cot b , Julie Mendret b , Anne Galarneau a,⇑ , Stephan Brosillon b,⇑ a Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, ENSCM, 8 rue de l’Ecole Normale, 34296 Montpellier Cedex 5, France b Université Montpellier 2, Institut Européen des Membranes, 2 place Eugène Bataillon, 34095 Montpellier Cedex 5, France article info Article history: Available online 9 October 2013 Dedicated to Dr. Michael Stöcker on the occasion of his retirement as Editor-in-Chief of Microporous and Mesoporous Materials. Keywords: Zeolite Ozone Hydroxyl radical 2,4-DMP AOP abstract Advanced oxidation processes (AOP) as ozonation coupled with inorganic materials have been recently demonstrated to be highly suitable for wastewater treatment. In petrochemical wastewa- ters, pollutants as alkylphenols are often detected. In this paper, we highlight the efficiency to couple ozone with zeolites as SOD, LTA and FAU-X for the degradation of 2,4-dimethylphenol (2,4-DMP). For process requirement the 3 zeolites were prepared as particles of 70 lm and 1 mm thanks to pseudomorphic transformation without binders. The zeolites were synthesized under their sodium (Na) form and potassium (K) ion-exchange was performed to enhance their basicity. By single ozonation (without zeolite) 100% of 2,4-DMP removal occurred in 25 min, but the pollutant is transformed into oxidized by-products corresponding to only 14% of the Total Organic Carbon (TOC) removal after 5 h. Adding zeolites to the ozonation process increased very slightly the kinetic of disappearance of the pollutant but increased the removal of its oxidation by-products, with 34% of TOC removal after 5 h. Among the zeolites, the best solid catalyst for ozonation was Na-LTA. Experiments with tert-butanol (t-BuOH) put in evidence that Na-LTA generates hydroxyl radicals from ozone, which increased the degradation of the by-products. No adsorption of 2,4-DMP and of the resulting oxidation by-products was detected by thermogravimetric analysis (TGA) on the materials after 5 h of ozonation. The TOC removal is consequently equivalent to the total minerali- zation of the organics into CO 2 . Ó 2013 Elsevier Inc. All rights reserved. 1. Introduction Industrial petrochemical wastewaters contain aromatic com- pounds such as polycyclic aromatic hydrocarbons (PAHs), ben- zene–toluene–ethylbenzene–xylene (BTEX) and phenols. In petrochemical effluents, 2,4-dimethylphenol (2,4-DMP) is a typical pollutant, which derived from the cresol part of fractional distilla- tion and extraction with aqueous alkaline solutions [1] and has been chosen as test molecule for our study. Nowadays, more attention has been paid in the removal of these pollutants with the evolution of water regulations given by the European water framework directive, which stated the improvement of all water bodies quality [2]. Fur- thermore, as reported by most of regulatory sources, 2,4-DMP and its oxidation by-products are known to have a high toxic character [3]. Efforts have been made for the development of more efficient wastewater treatment processes as adsorption or degradation by oxidation. Adsorption on coat fly for thermal effluents treatment led to 87% of 2,4-DMP removal after 48 h [4]. Advanced oxidation processes (AOP) appeared to be an adequate way for the elimination of this kind of refractory compounds by producing highly oxidative species [5,6]. For 2,4-DMP removal, different AOP have been used in literature. For example, the Fe 2+ /H 2 O 2 /UV process has reached 90% of pollutant removal after 1 h 40 min [6]. Recent studies have shown the positive effect of combining ozone with zeolites or activated car- bon to fasten xenobiotic pollutants removal in less than 1 h [7–9]. Zeolites are thermally and chemically more stable than activated carbon in presence of ozone [10] and therefore are more promising candidates for long term ozonation processes [9,11,12]. However, reaction mechanisms for pollutant degradation in zeolite/ozone process are still unclear and zeolite structure dependent. Some stud- ies point out the adsorption capacity of zeolites for pollutants, which are confined into the pore. However pollutant adsorption capacity in 1387-1811/$ - see front matter Ó 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.micromeso.2013.09.042 ⇑ Corresponding authors. Tel.: +33 4 67 16 34 68. E-mail addresses: anne.galarneau@enscm.fr (A. Galarneau), stephan.brosillo- n@iemm.univ-monpt2.fr (S. Brosillon). Microporous and Mesoporous Materials 189 (2014) 200–209 Contents lists available at ScienceDirect Microporous and Mesoporous Materials journal homepage: www.elsevier.com/locate/micromeso