Removal of lead from aqueous solution by magnetic modified dendrimer (Fe3O4@SiO2/(3-aminopropyl) triethoxysilane@dendrimer/benzaldehyde)

Abstract

Synthesis of a magnetite nanoadsorbent was reported in the study. In this regard, poly(amidoamine) (PAMAM) dendrimer (with generation 10)-functionalized Fe3O4@SiO2/APTES ((3-aminopropyl) triethoxysilane) was prepared, modified by benzaldehyde (BZ), and characterized by fourier-transfer-infrared (FTIR), vibrating-sample-magnetometer (VSM), field-emission-scanning-electron-microscope (FE-SEM), X-Ray-diffraction (XRD), thermal-gravimetric-analysis (TGA), and elemental analysis. The nanoadsorbent with VSM value of 35.3 emu/g was used to investigate adsorption of Pb(II) ions from aqueous solutions and this process relied on the solution pH, lead concentration, nanoadsorbent dose, contact time, and temperature. The results revealed the maximum adsorption efficiency of 97.56% in pH = 6, initial lead concentration = 160 mg L−1, adsorbent dose of 15 mg, contact time = 60 min, and temperature = 45 °C. The adsorption isotherm and kinetic models of Pb(II) removal followed the Freundlich model and pseudo-second-order, respectively. The adsorption was endothermic and spontaneous, which was exhibited by the thermodynamic parameters. This research suggests that the nanoadsorbent can be considered for the other metal ions removal from wastewater treatment.