Treatment of Polluted Water Resources Using Reactive Polymeric Hydrogel H. A. Shawky, 1 M. H. El-Sayed, 1 A. El-Hag Ali, 2 M. S. Abdel Mottaleb 3 1 Desert Research Center, El Matariya, Cairo, Egypt 2 National Center for Radiation Research and Technology, Nasr City, Cairo, Egypt 3 Chemistry Department, Faculty of Science, Ain Shams University, Egypt Received 5 March 2005; accepted 22 August 2005 DOI 10.1002/app.23017 Published online in Wiley InterScience (www.interscience.wiley.com). ABSTRACT: An experimental work was conducted to study the performance of the already prepared polyvinyl pyrrolidone/acrylic acid (PVP/AAc) copolymer hydrogel to chelate heavy metals from bulk solution. Studies of the binding capacity, adsorption isotherm, and adsorption ki- netic experiments showed that PVP/AAc copolymer hydro- gel has high binding capacities and good adsorption kinetic properties for the metal ions under investigation. The ad- sorption isotherms of such metal ions on the copolymer exhibit a Langmuir-type equation. The chelated copolymers were characterized by FTIR and XRD. Technical feasibility for the uses of the prepared PVP/AAc hydrogel for the treatment of polluted samples; collected from different wa- ter resources in Helwan area (Egypt) was investigated. The evaluation of the system was performed by a complete analysis of water samples before and after the treatment process. The results showed a promising possibility for pro- ducing water of better quality in the area under investiga- tion, using such prepared hydrogel. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3966 –3973, 2006 Key words: chelating hydrogel; adsorption isotherms; water treatment INTRODUCTION Helwan area is a suburb in south Cairo, on the east bank of the Nile River. The area is characterized by the pres- ence of many water resources such as the River Nile, irrigation canals, the groundwater wells, and the sulfur and mineral springs. 1–3 These water resources are used for drinking, domestic, agricultural, and industrial pur- poses as well as for medical treatment. Nowadays, the area is considered one of the industrial forts in Egypt because of some huge industrial projects such as iron and steel, cement, and galvanization industries. With the progressive increase of industrial activities, the area un- der consideration suffered from deterioration of the quality of surface and ground waters because of heavy metals pollution from the industrial waters. 4 The removal of such toxic metal ions from industrial wastewaters has received much attention in recent years because they cause health hazards in human beings and animals. Various methods, such as ion- exchange, reverse osmosis, and electrodialysis tech- niques, have been developed for the removal and recovery of heavy metal ions from sewage and indus- trial wastewater. 5–10 Traditional chemical precipita- tion can be envisaged, but the generation of precipi- tated bulky hydroxides and colloidal particles is a major disadvantage. 11,12 The search for an effective method of removing such toxic heavy metal ions requires the consideration of un- conventional materials and processes. Polymeric hydro- gels acquire a great interest in the field of water purifi- cation due to the facility of incorporation of different chelating groups into the polymeric networks and their chemical and thermal stability, easy separation from the reaction medium leading to operational flexibility, and their facial regenerability. 13–15 Hydrogels may be pre- pared by treating the aqueous solution of hydrophilic polymers and monomers with -ray 16 or chemical initi- ators. 17 Among these methods, -ray-induced simulta- neous polymerization and crosslinking is advantageous over the others. This technique is generally termed a “clean technique,” not requiring extra chemicals and without leaving any unwanted residues. The aim of the present study was to investigate the applicability of the already prepared 13 chelating poly- (vinyl pyrrolidone/acrylic acid) (PVP/AAc) copoly- mer hydrogel for treatment of the polluted water sam- ples collected from Helwan area. EXPERIMENTAL Materials PVP/AAc gels of molar composition (80/20) were prepared by -radiation-induced copolymerization Correspondence to: H. A. Shawky (hosamshawky@ hotmail.com). Journal of Applied Polymer Science, Vol. 100, 3966 –3973 (2006) © 2006 Wiley Periodicals, Inc.