A New Porous Chelating Fiber: Preparation, Characterization, and Adsorption Behavior of Pb(II)

Abstract

A new porous chelating fiber (PE-MA-NN) was prepared with polyethylene for the removal of Pb(II) from water. Scanning electron microscopy (SEM), contact angle, Brunauer–Emmett–Teller (BET) surface area, Fourier transform infrared (FT-IR), and 13C nuclear magnetic resonance (13C NMR) were used to characterize PE-MA-NN. The batch kinetic study indicated that the adsorption of Pb(II) could be well-fitted by a pseudo-second-order equation, suggesting intraparticle diffusion process as the rate-limiting step of the adsorption process. By using the Elovich equation, the initial adsorption rate of Pb(II) onto PE-MA-NN was calculated to be 394.084 mg (g min)−1. The Langmuir equation fit the experimental data well, and the monolayer saturation adsorption value was more than 500 mg g–1 for Pb(II). When the temperature was increased within the range of 278–308 K, the adsorption entropy changes of PE-MA-NN were from ∼95.30 J mol–1 K to ∼96.01 J mol–1 K. Although the presence of Ca2+ in solution had a negligible effect on the removal of Pb(II), PE-MA-NN could retain over 90% of its adsorption capacity, even if the Ca2+ concentration was up to 280 mg L–1. Both 1 M HCl and 0.1 M EDTA solution could be used as effective eluants to desorb the Pb(II) that has been adsorbed by PE-MA-NN, and the adsorption capacity could still be maintained at a high level at the fifth cycle.