Journal of Materials Science and Engineering B 1 (2011) 421-432 Formerly part of Journal of Materials Science and Engineering, ISSN 1934-8959 Performance Evaluation of the Fe-IR-120(Na)-DEHPA Impregnated Resin in the Removal Process of As(V) from Aqueous Solution Mihaela Ciopec 1 , Adina Negrea 1 , Lavinia Lupa 1 , Corneliu Davidescu 1 , Petru Negrea 1 and Paula Sfârloagă 2 1. Faculty of Industrial Chemistry and Environmental Engineering, University “Politehnica” Timisoara, Piata Victoriei No.2, Timisoara 300006, Romania 2. National Institute for Research and Development in Electrochemistry and Condensed Matter, Timisoara, Plautius Andronescu No.1, Timisoara 300224, Romania Received: April 09, 2011 / Accepted: April 26, 2011 / Published: September 25, 2011 Abstract: In the present paper the performance of a new functionalized material Fe-IR-120(Na)-DEHPA in the removal process of As(V) from aqueous solutions, has been investigated. The new material was obtained trough impregnation of Amberlite IR-120(Na) with di(2-ethylhexyl) phosphoric acid (DEHPA) trough the dry method. Trough impregnation of the Amberlite IR-120(Na) was obtained a resin with two functional groups which was further loaded with Fe(III) ions because of the high affinity of arsenic towards iron. The physicochemical methods of analysis (FTIR spectroscopy, EDX and SEM) approved that the impregnation with DEHPA and the iron loading, respectively, occurred. By applying the kinetic model to the experimental data it was found that the removal of As(V) ions by Fe-IR-120(Na)-DEHPA follows the pseudo-second-order rate kinetics. The linear Langmuir and Freundlich isotherm models were used to represent the experimental data and these could be well interpreted by the Langmuir isotherm. R L values between 0 and 1.0 further indicate a favorable adsorption of As(V) ions onto Fe-IR-120(Na)-DEHPA. The maximum As(V) ions uptake calculated from Langmuir model was 21.8 µg/g. Key words: Amberlite IR-120(Na), impregnation with DEHPA, Fe(III) ions loading, As(V) removal, kinetic studies. 1. Introduction The contamination of water resources with arsenic is a serious worldwide environmental problem, due to its high toxic effect on plants, animals and humans [1, 2]. The symptoms of chronic poisoning on human beings are numerous: skin cancer, liver, lung, kidney, and bladder cancer as well as conjunctivitis, hyperkeratosis, and in severe cases gangrene in the limbs and malignant neoplasm [3-5]. Therefore the maximum permissible limit in drinking water according to World Health Organization (WHO) is 10 µg/L [6-9]. Many separation techniques have been proposed for the removal of arsenic from aqueous solutions, which Corresponding author: Mihaela Ciopec, Ph.D., scientific researcher, research field: functionalized materials in environmental protection. E-mail: mihaela.ciopec@chim.upt.ro. include oxidation-reduction, precipitation, co-precipitation, adsorption, electrolysis and cementation, solvent extraction, ion-exchange, ion flotation, biological processing and sorption [7-20]. Among these methods, adsorption and ion exchange are highly popular and have been widely practiced for toxic element removal [1-10]. Sorbents of different types like biomaterials, metal oxide/hydroxide, zeolite, activated carbon, laterite etc. have been used by workers for arsenic removal [1-10]. Organic ion exchange resins were found more suitable for the removal of toxic elements from dilute solution, due to their faster kinetics, ease of regeneration and high adsorption capacity [21-26]. While a number of studies have been reported for the removal of the toxic elements onto Amberlite XAD series impregnated with