Thiol-functionalized electrospun polyacrylonitrile nanofibrous membrane for highly efficient removal of mercury ions

Mercury ions pollution has threatened people's health. Conventional nano-adsorbents suffer from the aggregation and later separation, novel adsorbent with high adsorption performance and easy recover properties is highly needed. In this study, thiol-functionalized electrospun polyacrylonitrile (PAN) nanofibrous membrane was obtained and used as easy recovery adsorbent for mercury ions. The morphologies and chemical composition were studied using SEM, TEM, ATR-FTIR, XRD and XPS. The results indicated that mercury adsorption performance was pH sensitive and the optimal pH range for mercury ions adsorption was about 5.5-6.0. The adsorption equilibrium reached within 25 min, and the adsorption process can be described using the pseudo-second-order model. Isotherm data fitted well to the Langmuir isotherm model. After adsorption of mercury ions, the thiol-functionalized nanofibrous membranes can be regenerated, and the adsorption efficiency maintained up to 90% after three times of usage. (C) 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.