TY  - JOUR
AU  - Marjanović, Vesna
AU  - Lazarević, Slavica
AU  - Janković-Častvan, Ivona
AU  - Potkonjak, Branislav
AU  - Janaćković, Đorđe
AU  - Petrović, Radomir
PY  - 2011
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/4085
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
> functionalized natural sepiolite > acid-activated sepiolite > 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. 8.0mg Cr(VI) per
g of functionalized acid-activated sepiolite at initial pH 3, when the pH of solution reached 4.7, and
ca. 2.7mg 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
T2  - Chemical Engineering Journal
T1  - Chromium (VI) removal from aqueous solutions using mercaptosilane functionalized sepiolites
VL  - 166
IS  - 1
SP  - 198
EP  - 206
DO  - 10.1016/j.cej.2010.10.062
ER  - 

@article{
author = "Marjanović, Vesna and Lazarević, Slavica and Janković-Častvan, Ivona and Potkonjak, Branislav and Janaćković, Đorđe and Petrović, Radomir",
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
> functionalized natural sepiolite > acid-activated sepiolite > 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. 8.0mg Cr(VI) per
g of functionalized acid-activated sepiolite at initial pH 3, when the pH of solution reached 4.7, and
ca. 2.7mg 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",
journal = "Chemical Engineering Journal",
title = "Chromium (VI) removal from aqueous solutions using mercaptosilane functionalized sepiolites",
volume = "166",
number = "1",
pages = "198-206",
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., 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, Vesna, Lazarević, Slavica, Janković-Častvan, Ivona, Potkonjak, Branislav, Janaćković, Đorđe, Petrović, Radomir, "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 . .