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چکیده
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Abstract: Graphene with its exceptional properties has been widely used in the preparation of next generation functional nanocomposites[1]. We have modified graphene nanoparticles With aluminium oxide(alumina) and used these for selective solid-phase extraction of trace amounts of lead metal ions. Heavy metal ions are toxic pollutants which exist in waste watersand are concerning for industries and environmental organizations all over the world[2]. The nanoparticles were characterized by FT-IR , XRD and SEM. Extraction time, amount of adsorbent ,pH value, type, volume, concentration of eluent and elution time were found to be critical factors for uptake. Quantitative extraction of trace amounts of Pb(II) from solutions was accomplished at an optimal pH value of 7 within 10 min. The metal ions were eluted from the sorbent with hydrochloric acid 1M.The ions were then determined by FAAS. The resulting calibration curve is linear in the concentration range of 8–1200 ȝgLí1 and limit of detection (LOD) was 4 ngmLí1 , while the relative standard deviation (RSD) was 1.44% (at 100µg L-1 Pb level and n=8). The enrichment factor is 22.65 (for 50 mL samples),and the adsorbent can be used for at least 5 cycles of preconcentration and elution. The adsorbent was successfully applied to the rapid extraction of trace quantities of Pb (II) ion in tea, rice, tomato , kohl and water samples.
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