Quang, Dang VietLee, Jae EunKim, Jong-gilKim, You NaShao, Godlisten N.Kim, Hee Taik2016-05-162016-05-162012-10-22http://hdl.handle.net/20.500.11810/2077Full text can be accessed at the following link http://www.sciencedirect.com/science/article/pii/S0032591012006924Thiol-functionalized silica that has been used to remove heavymetal from an aqueous solution and supportmetallic nanoparticles is usually synthesized by reflux in an organic solvent containing 3-mercaptopropyltrimethoxysilane (MPTMS). In this paper, we report a gentle method for grafting thiol-functional groups onto silica gel by an aging process that does not require mixing and refluxing in an organic solvent. Silica gel was synthesized by a sol–gel method from H2SO4 (40%) and sodium silicate, which was crushed into beads with sizes ranging from 180 to 450 μm. Silica beads (50 g) were mixed with 75 mL of a functionalization solution consisting of MPTMS, H2O, and C2H5OH and aged at 50 °C for 36 h in a box dryer. The success of the functionalization process was confirmed by FT-IR, BET, SEM and elemental analyses. The functionalization solution was percolated into pores and thiolfunctional groups were grafted onto the surface and pore walls of the silica beads. The ability of these functionalized silica beads to adsorb silver ionswas determined by the Langmuir isotherm equationwith amaximumadsorption of 75.8 mg/g. Silver nanoparticles with sizes ranging from 2 to 6 nmformed by chemical reductionwere located inside the pores and on the surfaces.en-USJournal Article, Peer Reviewed