TY  - JOUR
AU  - Marjanović, V.
AU  - Lazarević, Slavica
AU  - Janković-Častvan, Ivona
AU  - Potkonjak, Branislav
AU  - Janaćković, Đorđe
AU  - Petrović, Rada
PY  - 2011
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1916
AB  - Natural and acid-activated sepiolite samples were functionalized with (3-Mercaptopropyl)trimethoxysilane. By X-ray powder diffraction, Fourier transform infrared spectroscopy, and differential thermal analysis it was shown that functionalization of sepiolites by grafting silane reagents occurs mainly on the surface, whereby their crystalline structure remained unchanged. The efficiency of the adsorbents in Cr(VI) removal from aqueous solutions follows the order: functionalized acid-activated sepiolite  gt  functionalized natural sepiolite  gt  acid-activated sepiolite  gt  natural sepiolite. As the number of silanol groups on the sepiolite surface increased during the acid activation, the silane functionalization increased and this led to an increase in Cr(VI) adsorption. The adsorption capacity strongly depended on the pH of the solution from which the adsorption occurred. Maximum Cr(VI) removal was ca. 8.0 mg Cr(VI) per g of functionalized acid-activated sepiolite at initial pH 3, when the pH of solution reached 4.7, and ca. 2.7 mg Cr(VI) per g of functionalized natural sepiolite at initial pH 2, when the pH of the solution reached 2.5. Cr(VI) removal by the functionalized sepiolites was mainly attributed to electrostatic attraction between the protonated mercapto groups and the negatively charged Cr(VI) species. The sorption isotherms showed that Cr(VI) removal by both functionalized sepiolites for all initial investigated solution pH values is well described using the Dubinin-Radushkevich model. The thermodynamic data suggest spontaneity of the major physical adsorption process at 298 K.
PB  - Elsevier Science Sa, Lausanne
T2  - Chemical Engineering Journal
T1  - Chromium (VI) removal from aqueous solutions using mercaptosilane functionalized sepiolites
EP  - 206
IS  - 1
SP  - 198
VL  - 166
DO  - 10.1016/j.cej.2010.10.062
ER  - 

@article{
author = "Marjanović, V. and Lazarević, Slavica and Janković-Častvan, Ivona and Potkonjak, Branislav and Janaćković, Đorđe and Petrović, Rada",
year = "2011",
abstract = "Natural and acid-activated sepiolite samples were functionalized with (3-Mercaptopropyl)trimethoxysilane. By X-ray powder diffraction, Fourier transform infrared spectroscopy, and differential thermal analysis it was shown that functionalization of sepiolites by grafting silane reagents occurs mainly on the surface, whereby their crystalline structure remained unchanged. The efficiency of the adsorbents in Cr(VI) removal from aqueous solutions follows the order: functionalized acid-activated sepiolite  gt  functionalized natural sepiolite  gt  acid-activated sepiolite  gt  natural sepiolite. As the number of silanol groups on the sepiolite surface increased during the acid activation, the silane functionalization increased and this led to an increase in Cr(VI) adsorption. The adsorption capacity strongly depended on the pH of the solution from which the adsorption occurred. Maximum Cr(VI) removal was ca. 8.0 mg Cr(VI) per g of functionalized acid-activated sepiolite at initial pH 3, when the pH of solution reached 4.7, and ca. 2.7 mg Cr(VI) per g of functionalized natural sepiolite at initial pH 2, when the pH of the solution reached 2.5. Cr(VI) removal by the functionalized sepiolites was mainly attributed to electrostatic attraction between the protonated mercapto groups and the negatively charged Cr(VI) species. The sorption isotherms showed that Cr(VI) removal by both functionalized sepiolites for all initial investigated solution pH values is well described using the Dubinin-Radushkevich model. The thermodynamic data suggest spontaneity of the major physical adsorption process at 298 K.",
publisher = "Elsevier Science Sa, Lausanne",
journal = "Chemical Engineering Journal",
title = "Chromium (VI) removal from aqueous solutions using mercaptosilane functionalized sepiolites",
pages = "206-198",
number = "1",
volume = "166",
doi = "10.1016/j.cej.2010.10.062"
}

Marjanović, V., Lazarević, S., Janković-Častvan, I., Potkonjak, B., Janaćković, Đ.,& Petrović, R.. (2011). Chromium (VI) removal from aqueous solutions using mercaptosilane functionalized sepiolites. in Chemical Engineering Journal
Elsevier Science Sa, Lausanne., 166(1), 198-206.
https://doi.org/10.1016/j.cej.2010.10.062

Marjanović V, Lazarević S, Janković-Častvan I, Potkonjak B, Janaćković Đ, Petrović R. Chromium (VI) removal from aqueous solutions using mercaptosilane functionalized sepiolites. in Chemical Engineering Journal. 2011;166(1):198-206.
doi:10.1016/j.cej.2010.10.062 .

Marjanović, V., Lazarević, Slavica, Janković-Častvan, Ivona, Potkonjak, Branislav, Janaćković, Đorđe, Petrović, Rada, "Chromium (VI) removal from aqueous solutions using mercaptosilane functionalized sepiolites" in Chemical Engineering Journal, 166, no. 1 (2011):198-206,
https://doi.org/10.1016/j.cej.2010.10.062 . .