Acrylic acid (AAc) grafted polyethylene terephthalate (PET) films were prepared by γ irradiation. The graft films showed little metal ion adsorption due to compact structure of the graft chains as shown by the scanning electron microscopy (SEM) images which restricted the access of metal ions to the functional groups. Therefore, the graft films were modified with KOH treatment for expansion of the graft chains to facilitate the access of metal ions to the functional groups. The modified films were used to study the selective Cu2+ adsorption from aqueous solution containing Cu2+, Co2+, and Ni2+. Langmuir and Freundlich isotherm models were used for interpretation of selective equilibrium adsorption data and Langmuir model showed better fitting with experimental data. Again pseudo-first-order and pseudo-second-order equations were used for interpretation of selective kinetic adsorption data and pseudo-second-order equation showed better prediction of experimental data. The adsorbent film showed high selectivity towards Cu2+ in presence of Cu2+, Co2+, and Ni2+ in the pH range of 1.5 to 4.5. Desorption and reuse of the adsorbent film were also studied which indicated that the film can be used repeatedly for selective Cu2+ sorption from aqueous solution. 1. Introduction In recent years, heavy metals have received much public attention as potential hazards for human life and health ignited by the well-known environmental destruction cases: Minamata disease (organic mercury poisoning) and itai-itai disease (cadmium poisoning) and the stricter environmental regulations on the discharge of heavy metals make it necessary to develop efficient and low cost technologies for their removal [1]. About heavy metal pollution it should be also realized that to prevent heavy metal poisoning, immediate detoxification of heavy-metal wastewater through appropriate treatment is essential. Because, unlike many organic pollutants, heavy metals are not decomposed by microbiological activity, rather heavy metals can be enriched by organisms and the type of bonding can be converted to more poisonous metal-organic complexes and the polluted areas can become widened by diffusion in the environment. But the conventional methods for removal of hazardous metal ions from wastewater such as precipitation, ion exchange, activated carbon adsorption, and electrolytic method have limitations like high cost, low removal rate or difficulty for regeneration, and reuse. Therefore, many researches focused on the study of alternative low-cost-effective adsorbents from sawdust [2], sporopollenin [3,
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