Poly(Amidoamine) Dendrimer Modified Superparamagnetic Nanoparticles as an Efficient Adsorbent for Cr(VI) Removal: Effect of High-Generation Dendrimer on Adsorption Performance

In this work, three different generations of Poly(amidoamine) dendrimers (PAMAM) decorated on magnetic Fe3O4 composites (Fe3O4@SiO2–G1, Fe3O4@SiO2–G3, Fe3O4@SiO2–G5) were fabricated and characterized by FTIR, XRD, TEM, TGA, VSM XPS. The obtained used for Cr(VI) removal. Batch adsorption studies showed that the reached equilibrium within 60 min, optimal pH was 3.0. result kinetics simulated pseudo-second-order model. isotherm well fitted with Langmuir Furthermore, thermodynamics calculations revealed process endothermic spontaneous. Importantly, capacity obeyed sequence Fe3O4@SiO2–G1 < Fe3O4@SiO2–G5 3 generation PAMAM (G3) Cr(VI). maximum theoretical (qm) Fe3O4@SiO2–G3 334.45 mg/g, removal ration remained above 89.5% after five cycles adsorption–desorption. Thus, is predicted to be an efficient adsorbent from aqueous solution, results can help in optimization during fabrication dendrimer modified adsorbents.