Designing three-dimensional half-embedded ES-PAN/AHCNs adsorption membrane for removal of Pb(Ⅱ), Cu(Ⅱ) and Cr(Ⅲ)

Abstract

The agglomeration of nanoscale carbon-based material with excellent large specific surface area and numerous active sites remains a challenging, which decreases the adsorption efficiency. Herein, a three-dimensional (3D) half-embedded architecture adsorbent membrane (ES-PAN/AHCNs) was designed to address this weakness by combining the small-sized activated hollow carbon nanospheres （AHCNs） with polyacrylonitrile (PAN) fiber. The 3D architecture precludes the agglomeration of AHCNs, while the half-embedded of AHCNs ensures structural stability of fiber adsorbents. The adsorption capacity and mechanism of ES-PAN/AHCNs membrane were investigated by using metal ions (Pb(Ⅱ), Cu(Ⅱ), Cr(Ⅲ)). Concretely, the adsorption capacity of ES-PAN/AHCNs membrane to Pb(Ⅱ), Cu(Ⅱ) and Cr(Ⅲ) were 192, 186 and 179 mg g−1, respectively, which was more than two times than that of AHCNs. Noticeably, the significant increase of adsorption capacity mainly benefits from the 3D half-embedded architecture, owing to that pure PAN fiber has negligible adsorption capacity. Moreover, the adsorption capability of ES-PAN/AHCNs membrane retained 82.1% after twelve adsorption-desorption cycles. The strategy of fabricating 3D half-embedded adsorbent membrane substantially expands the potential for AHCNs applications in the adsorption and water purification fields.