Modified aluminum scrap waste was used in the selective extraction of Hg(ii), and Cd(ii) ions. The aluminum scraps were modified with dibenzoylmethane, or isatoic anhydride, or 5-(2-chloroacetamide)-2-hydroxybenzoic acid. The modified aluminum sorbents were characterized by FT-IR, SEM, XRD, XPS, TGA, and elemental analysis. Modes of chelation between adsorbents and target metal ions were deduced via DFT. The highest adsorption capacity was observed for benzo-amino aluminum (BAA) toward Hg(ii), which reached 234.56 mg g-1, while other modified sorbents ranged from 135.28 mg g-1 to 229.3 mg g-1. Under the optimized conditions, the BAA adsorbent showed a lower limit of detection (1.1 mg L-1) and limit of quantification (3.66 mg L-1) for mercury ions than other sorbents. The prepared aluminum adsorbents also exhibited significant selectivities for Hg(ii) and Cd(ii) ions in the presence of competing metal ions.
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