Preparation of monodispersed mesoporous silica particles and their applications in adsorption of Au3+ and Hg2+ after mercapto-functionalized treatment

摘要

Colloidal suspensions of monodispersed nanoporous silica particles were first successfully synthesized by using small organic amine (N,N,N',N'-Tetrakis(2-hydroxyethyl)ethylenediamine) as basic catalyst; and then, the mercaptopropyl functionalized counterpart was also fabricated by co-condensation of mercaptopropyl silane and tetraethyl orthosilicate in a similar way. These nanoporous silica particles were characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), nitrogen adsorption-desorption and X-ray diffraction. Experimental results indicated that all the spherical nanoporus silica particles are uniform (with the size of about 30-40 nm) and possessed large specific surface area (about 500 m(2)/g), large pore volume (>1.6 cm(3)g(-1)) and narrow pore sizes distribution (<3 nm). Furthermore, the mercaptopropyl functionalized products served as adsorbent to efficiently remove Hg2+ and Au3+ ions in water. (C) 2015 Elsevier Inc. All rights reserved.