Chemical Engineering Journal 160 (2010) 176–184 Contents lists available at ScienceDirect Chemical Engineering Journal journal homepage: www.elsevier.com/locate/cej Comparative evaluation of polymer surface functionalization techniques before iron oxide deposition. Activity of the iron oxide-coated polymer films in the photo-assisted degradation of organic pollutants and inactivation of bacteria F. Mazille b , A. Moncayo-Lasso a , D. Spuhler b , A. Serra c , J. Peral c , N.L. Benítez a , C. Pulgarin b,∗ a Group of Advanced Oxidation Processes (GAOX), Department of Chemistry, Universidad del Valle, Cali, Colombia b Institute of Chemical Sciences and Engineering, SB, GGEC, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland c Departament de Quimica, Edifici Cn, Universitat Autonoma de Barcelona, E-08193 Bellaterra, Barcelona, Spain article info Article history: Received 5 January 2010 Received in revised form 15 March 2010 Accepted 16 March 2010 Keywords: Polymer surface modification Photo-Fenton SODIS Bacterial inactivation Photocatalytic functionalization abstract The preparation of iron oxide-coated polymer films and their photocatalytic activity in organic pollu- tants degradation and bacterial inactivation is described. Polyvinyl fluoride (PVF), polyethylene (PE) and polyethylene terephtalate (PET) films were used as catalyst supports. Polymer surfaces were function- alized by vacuum-UV radiation (V-UV) and radio-frequency plasma (RF-P); and also by photo-Fenton oxidation (P-FO) and TiO 2 photocatalysis (Ti-PC) in solution. These pre-treatments were performed to improve iron oxide adhesion on the commercial polymer surface. The functionalized polymers films (P f ) were afterward immersed in an aqueous solution for the deposition of iron oxide layer by hydrolysis of FeCl 3 . The photocatalytic activities of iron oxide-coated functionalized polymers films (P f -Fe oxide) pre- pared by different methods were compared during hydroquinone degradation in presence of H 2 O 2 . RF-P and Ti-PC pre-treated polymers showed significantly higher photocatalytic activity and long-term sta- bility during processes leading to pollutant abatement, if compared with not treated ones (NT), although similar leaching of iron was observed for all the materials. PET bottles (PET b ) were used as reactor and cata- lyst supports. The produced PET b f -Fe oxide surfaces were efficient in photo-assisted bacterial inactivation in the presence of H 2 O 2 , and no dissolved iron species were detected in solution. © 2010 Elsevier B.V. All rights reserved. 1. Introduction The photo-assisted Fenton oxidation is a promising alternative to obtain drinking water from contaminated water since it leads to water remediation under solar light irradiation. Homogeneous photo-Fenton process (Fe 2+ /H 2 O 2 /light) is a method for the treat- ment of water containing bio-recalcitrant organic pollutants [1] that has also shown to be effective in bacterial disinfection [2–5]. However, this process has some disadvantages such as the need of a narrow operational pH range (pH 3–5) and sludge formation. Therefore, an end of pipe treatment is needed to neutralize pH and to recover catalyst since the maximum dissolved iron concentra- tion allowed in the European Union legislation for drinking water is 0.2 mg/L [6]. To overcome these limitations the use of dispersed iron oxides particles such as hematite, goethite or akaganeite as solid photo-Fenton catalyst has been proposed [7]. The immobilization of iron oxides on supports and the evaluation of their photocatalytic ∗ Corresponding author. Tel.: +41 21 693 47 20; fax: +41 21 693 61 61. E-mail address: cesar.pulgarin@epfl.ch (C. Pulgarin). activity have shown growing interest during the present decade [8–14]. Solar water disinfection (SODIS) is a low cost method for treating microbial contaminated drinking water in transparent plastic bot- tles [15]. Nevertheless this method presents some disadvantages such as temperature dependency and re-growth of microorganism. The application of photo-Fenton could solve the SODIS limitations and lead to the simultaneous disinfection and degradation of xeno- biotics and natural organic matter. The use of polymer film or bottles as supports for iron oxides deposition was chosen for this study although it induces several drawbacks that have to be overtaken: (i) commercial polymer films surfaces are slick, limiting iron oxide crystal nucleation and its adhesion to the substrate; (ii) since the point of zero charge of iron oxide is around pH 8 [16] their surface is positively charged at neutral and acidic pHs. Thus, the presence of electron donor groups as carboxylic acids on polymer support surface is required to bind strongly iron oxide particles; and (iii) polymer films are destroyed under high temperature and are slowly degraded under solar irradiation. Although commercial available polymers have surface roughness, electron donor groups, relatively high melting point and high stability under solar light, many commonly used 1385-8947/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.cej.2010.03.035