Novel magnetic polyethersulfone-polyethyleneimine-based microbeads for removal of lead ions from water: Kinetics and thermodynamics

Abstract

In this study, a novel magnetic microbead adsorbent (M−PES−PEI) was made using magnetic iron oxide (MNPs), polyethersulfone (PES), and polyethyleneimine (PEI)to remove the lead ions (Pb2+) from drinking water. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FTIR) methods were used to analyze the M−PES−PEI microbeads. Adsorbent dosage (20 mg), contact time (90 min), and solution pH ∼ 5 as the effective parameters on experimental conditions were examined and 91% removal of Pb2+ was obtained using 50 mg of microbeads. Adsorption models based on isotherms, kinetics, and thermodynamics were used to simulate the adsorption of Pb2+ over M−PES−PEI. The pseudo-second-order as the kinetic model was fitted to the adsorption data at different times (R2 > 0.97). In the isotherm study, the Freundlich model shows a higher R2 (0.99) value than the Langmuir model at different concentrations. After 90 min of contact time at room temperature, the maximum adsorption capacity was 312 mg.g−1 with physical mechanism.