Preparation, characterization of thiol-functionalized silica and application for sorption of Pb2+ and Cd2+

Engineering and optimization of nano- and mesoporous silica fibers using sol–gel and electrospinning techniques for sorption of heavy metal ions

“…For sorption of Cd 2+ , saturation was achieved within 30 min on nSiO 2 @mSiO 2 and 10 min on SHASiO 2 @ mSiO 2 , respectively, while for Pb 2+ , the saturation time became even shorter, within 10 min for both nSiO 2 @mSiO 2 and SHASiO 2 @ mSiO 2 . Two kinetic models, namely Lagergren's first-order rate equation and pseudo-second-order kinetic model, were applied to fit the experimental data [7].…”

“…For sorption isotherm, two models, Langmuir isotherm and Freundlich isotherm models, are commonly adopted to fit the experimental data [7]. The results of sorption isotherm measurements and the corresponding fit curves are shown in Fig.…”

“…In the past decade, many investigations have been conducted on mesoporous SiO 2 as sorbent for removal of hazardous metal ions, such as Pb 2+ , Cd 2+ , and Hg 2+ , from wastewater [1][2][3][4][5][6][7][8][9]. To be effective heavy metal ion sorbents, the material should have high sorption capacity and be easily separated [10].…”

Functionalized diatom silica microparticles for removal of mercury ions

“…A similar composition, but with a noticeable increase in C, S or N concentration was deduced from the XRF analysis of organosilane-modified samples. Figure 3 shows the infrared absorption spectra of the pristine and organosilane-modified diatoms (MPTMS-DE, −1 are associated with the asymmetric and symmetric stretching modes of the -CH 2 -moiety, respectively, which is directly related to the carbon chain of organosilane molecules [29,30]. In the spectra of MPTMS-DE, the -SH stretching vibration occurs at about 2566.8 cm −1 and is associated with the functional group of the adsorbed MPTMS [29].…”

Adsorption of Pb(II) and Cu(II) metal ions on functionalized large-pore mesoporous silica

“…Several methods have been developed to remove heavy metal ions from aqueous solutions, and adsorption is one of the most frequently used techniques. The adsorbents adopted in the literature include waste dust (Wang and Lin 2008;Amarasinghe and Williams 2007;Sharaf and Hassan 2014;Singh et al 2014), clays (Ö zcan et al 2009), polymer fibers (Deng et al 2003), and porous silica (Feng et al 1997;Liu et al 2000;Lam et al 2006;Walcarius et al 2003;Vasudevan et al 2011;Blitz et al 2007;Aguado et al 2009Aguado et al , 2008Xia et al 2010;Da'na and Sayari 2011;Shahbazi et al 2011;Liang et al 2009;Kao et al 2008;Chandra et al 2010). Still, researches toward the development of efficient adsorbents for the removal of heavy metals from wastewater are of great concern.…”