Highly hydrophobic ceramic membranes applied to the removal of volatile organic compounds in pervaporation Joanna Kujawa a , Sophie Cerneaux b , Wojciech Kujawski a,⇑ a Nicolaus Copernicus University, Faculty of Chemistry, 7 Gagarina St., 87-100 Torun, Poland b Institut Europeen des Membranes, UMR 5635, Place Eugene Bataillon, 34095 Montpellier Cedex 5, France highlights  TiO 2 , Al 2 O 3 and ZrO 2 ceramic membranes were hydrophobized by using fluorosilanes.  Efficient removal of VOCs was obtained using hydrophobic pervaporation (PV).  Hydrophobic ceramic membranes were successfully applied for removal of MTBE and EtAc.  Hydrophobized TiO 2 membrane removed VOCs with the highest efficiency. graphical abstract article info Article history: Received 18 July 2014 Received in revised form 22 August 2014 Accepted 26 August 2014 Available online 4 September 2014 Keywords: Pervaporation Ceramic membranes Hydrophobicity Volatile organic compounds MTBE Ethyl acetate abstract Highly hydrophobic titania, alumina and zirconia porous ceramic membranes were prepared by grafting of C 6 F 13 C 2 H 4 Si(OEt) 3 (C6) and C 12 F 25 C 2 H 4 Si(OEt) 3 (C12) molecules and subsequently applied in pervapo- ration (PV) process for removal of volatile organic compounds (methyl tert-butyl-ether/MTBE and ethyl acetate/EtAc) from binary aqueous solutions. Transport of pure water through pristine and hydrophob- ized membranes were compared. The transport and separation properties in PV process of investigated hydrophobic membranes were discussed. The influence of the membrane materials, pore size of the membranes as well as conditions of the grafting procedure (time and type of molecules) on the pervapo- rative properties was presented. All investigated membranes were selective toward organic compounds. The highest efficiency was found for the TiO 2 membranes, independently of the utilized system and applied grafting molecules. Better transport and selective properties were observed for membrane mod- ified by C6 molecules than by C12 ones. TiO 2 and ZrO 2 membranes modified by C6 were characterized by high b separation factors 84 (TiO 2 ) and 56 (ZrO 2 ). The least effective membrane was alumina one. Addi- tionally, the influence of contact of different solvents (water, EtAc and MTBE) with the hydrophobic layer was discussed. It was found that in the presence of organic compounds in the aqueous solution, the con- formation of hydrophobic chains is changing from tangled to straight one. Ó 2014 Elsevier B.V. All rights reserved. 1. Introduction Volatile organic compounds (VOCs) are widely used in the man- ufacture of various products including refrigerants, plastics, adhesives, paints and petroleum products [1–8]. To eliminate or recover these compounds from wastewaters, the classical separa- tion processes like distillation are usually applied, regardless high energy demand or formation of azeotropes [2,6,8–13]. New regulations regarding chemical emission limits in particular volatile organic compound (VOC) demand more efficient and less costly technologies. Recently, various techniques for http://dx.doi.org/10.1016/j.cej.2014.08.092 1385-8947/Ó 2014 Elsevier B.V. All rights reserved. ⇑ Corresponding author. Tel.: +48 56 611 43 15; fax: +48 56 654 24 77. E-mail address: kujawski@chem.umk.pl (W. Kujawski). Chemical Engineering Journal 260 (2015) 43–54 Contents lists available at ScienceDirect Chemical Engineering Journal journal homepage: www.elsevier.com/locate/cej