نوع مقاله : مقاله پژوهشی
موضوعات
عنوان مقاله English
نویسندگان English
Heavy metals such as nickel in aqueous environments pose significant risks to both human health and natural ecosystems, owing to their pronounced toxicity, environmental persistence, and tendency to bioaccumulate within food chains. In this study, a novel magnetic graphene oxide nanocomposite functionalized with an allylamine–vinyl imidazole copolymer (Poly-g-MGO) was synthesized and utilized as an efficient adsorbent for removing Ni(II) ions from aqueous solutions. Optimum adsorption conditions were established through batch experiments at pH=7, a contact time of 80 minutes, an adsorbent dosage of 0.25 g L−1, and a temperature of 298 K, with an initial Ni(II) concentration of 20 mg L−1. The removal efficiency of Ni(II) reached 90% under these conditions. The adsorption equilibrium data were best described by the Freundlich isotherm model, indicating a multilayer adsorption process on a heterogeneous surface. The Langmuir model estimated a maximum monolayer adsorption capacity of 133.366 mg g−1. The adsorption capacity diminished as the temperature increased from 298 to 328 K, confirming the exothermic nature of the process. Kinetic studies revealed that the adsorption followed a pseudo-second-order kinetic model, with intra-particle diffusion playing a dominant role in the adsorption mechanism. The adsorbent's practical applicability was further evaluated in real water samples, including tap water, Zayandeh-rood river water, and spent caustic industrial wastewater. The lower removal efficiency in industrial wastewater was attributed to the competitive adsorption of coexisting ions. These findings demonstrate the high capability of Poly-g-MGO for Ni(II) removal and its potential for treating contaminated aqueous samples.
کلیدواژهها English