Arab J Sci Eng DOI 10.1007/s13369-017-2857-8 RESEARCH ARTICLE - CHEMICAL ENGINEERING Impact of TiO 2 –Cation Exchange Resin Composite on the Removal of Ethyl Violet Fazia Agueniou 1 · Derradji Chebli 1 · Abdelbaki Reffas 2 · Abdallah Bouguettoucha 1 · Yacine Benguerba 1 · Lidia Favier 3 · Abdeltif Amrane 3 Received: 17 November 2016 / Accepted: 5 October 2017 © King Fahd University of Petroleum & Minerals 2017 Abstract Adsorption capacity and photocatalytic perfor- mance of a mixture of TiO 2 and a cation exchange resin were assessed by measuring the removal of the cationic dye ethyl violet (EV) from water. Highest adsorption of EV was achieved at pH 3 due to the increase in number of positive charges of the EV molecule. However, adsorp- tion decreased at higher pH. The adsorption kinetics at pH 3 could be accurately described by means of a pseudo-second order kinetic model. Experimental adsorption equilibrium data at pH 3 fitted the Langmuir model more accurately than the Sips and Freundlich models. Photocatalysis exper- iments indicated that the EV elimination was higher with B Abdallah Bouguettoucha abd_bouguettoucha@yahoo.fr Fazia Agueniou fazia.agueniou@yahoo.com Derradji Chebli derradji_chebli@yahoo.fr Abdelbaki Reffas Abdelbakireffas@gmail.com Yacine Benguerba benguerbayacine@yahoo.fr Lidia Favier lidia.favier@ensc-rennes.fr Abdeltif Amrane abdeltif.amrane@univ-rennes1.fr 1 Laboratoire de Génie des Procédés Chimiques, Département de Génie des Procédés, Faculté de Technologie, Université Ferhat Abbas, Sétif-1, 19000 Sétif, Algérie 2 Laboratoire des Matériaux Inorganiques, Faculté des sciences, Université Mohamed Boudiaf - M’sila, M’sila, Algérie 3 CNRS, UMR 6226, Ecole Nationale Supérieure de Chimie de Rennes, Université de Rennes 1, Avenue du Général Leclerc, CS 50837, 35708 Rennes Cedex 7, France the mixture of cation exchange resin and TiO 2 than with pure TiO 2 . The description of experimental photocataly- sis data by means of the Langmuir–Hinshelwood model was improved by introducing a power parameter in the original model. From the modified Langmuir–Hinshelwood model, it could be derived that the addition of increas- ing resin concentrations to a constant TiO 2 concentration enhanced the photocatalytic rate constant; however, UV light penetration in the solution was impeded beyond a given resin amount. Pseudo-first-order kinetics showed poor fit of experimental photocatalysis data except for low EV concentration (< 35 mg/L) at high resin dosage. A syn- ergistic effect between adsorption and photocatalysis was seen upon combining the TiO 2 . This composite was more efficient for the removal of the dye than the use of TiO 2 alone. Keywords Adsorption · Cation exchange resin · Ethyl violet · Hybrid process · TiO 2 · UV photocatalysis 1 Introduction Effluents from textile industries vary depending on the kind of the manufactured textiles [1]. Some dyes and their by- products, such as aromatic amines, are potentially toxic. [2, 3]. Anaerobic metabolites of azo dyes can be carcino- genic [4]. Therefore, several processes have been used for the elimination of textile dyes, including physical, chemical and biological methods [5]. Physical methods used to remove dyes are adsorption, flocculation, coagulation, electro-flocculation, reverse osmo- sis, ultrafiltration [6, 7], ion exchange and membrane pro- cesses [8]. The main drawback of adsorptive separation processes such as ion exchange is the need for regeneration, 123