Preparation and application of amino functionalized mesoporous nanofiber membrane via electrospinning for adsorption of Cr~(3+) from aqueous solution

摘要

Novel amino (-NH_2) functionalized mesoporous polyvinyl pyrrolidone (PVP)/SiO_2 composite nanofiber membranes were fabricated by a one-step electrospinning method using poly (vinyl alcohol) and tetraethyl orthosilicate (TEOS) mixed with cationic surfactant, cetyltrimethyl ammonium bromide (CTAB) as the structure directing agent. Ureidopropyltriethoxysilane was used for functionalization of the internal pore surfaces. The membranes were characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) images, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), element analyzer and N_2 adsorption-desorption isotherms. The nanofiber diameters, average pore diameters and surface areas were 100-700 nm, 2.86 nm and 873.62 m~2/g, respectively. These mesoporous membranes functionalized with -NH_2 groups exhibited very high adsorptions properties based on the adsorption of Cr~(3+) from an aqueous solution. Equilibrium adsorption was achieved after approximately 20 min and more than 97% of chromium ions in the solution were removed. The membrane could be regenerated through acidification.