Electrospun polyacrylonitrile/hydroxyapatite composite nanofibrous membranes for the removal of lead ions from aqueous solutions

Abstract

Novel polyacrylonitrile/hydroxyapatite (PAN/HAP) composite nanofibrous membranes were successfully prepared via electrospinning. Scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffractometry were used to characterize the PAN/HAP nanofibrous membranes. The highest adsorption capacity of 111.92 mg g⁻¹ was reached at an adsorbent dosage of 1 g L⁻¹, with an original lead ion concentration of 400 mg L⁻¹, and after a duration time of 300 min. Pseudo-second-order kinetics and Langmuir isotherm models were applicable to represent the adsorption process and reveal the mechanism of the membranes, with monolayer adsorption being identified. In regeneration experiments, 82.26% of the accumulation capacity was retained after five adsorption–desorption cycles. Therefore, the PAN/HAP nanofibrous membranes can be used as excellent and reusable adsorbents for Pb²⁺ removal.