Rational Engineering of 3D Petal-Like Porous magnetic SnFe₂O₄/Boron Nitride/NiAl-LDH Composite for Pb(II) Ions Removal

The growing issue of Pb 2+ ions contamination in marine environments necessitates the development of effective adsorbents to significantly mitigate this ecological challenge. In response, a novel composite material comprising layered double hydroxide (LDH), boron nitride (BN), and tin ferrite (SnFe 2 O 4 ) was synthesized for the removal of Pb 2+ ions. The synthesized SnFe 2 O 4 /BN/NiAl-LDH composite was characterized using FTIR, XRD, ZP, SEM, and XPS techniques. Pb 2+ ions removal reached equilibrium within 30 minutes, with a removal efficiency of 95.42%. Pb 2+ removal efficiency increased progressively in the following order based on the data: SnFe 2 O 4 /BN/NiAl-LDH (1:1) > SnFe 2 O 4 /BN/NiAl-LDH (3:1) > SnFe 2 O 4 /BN/NiAl-LDH (1:3). Furthermore, the experimental data were consistent with the Langmuir and Freundlich isotherms, as well as the pseudo-second-order kinetic model, with a maximum adsorption capacity of 434.8 mg/g. Notably, the composite retained over 70% removal efficiency after five cycles, demonstrating its efficient recyclability. In summary, SnFe 2 O 4 /BN/NiAl-LDH exhibits rapid and efficient adsorption, easy separation, and excellent recyclability.