TY  - JOUR
AU  - Milutinovic-Nikolic, A.
AU  - Maksin, Danijela D.
AU  - Jovic-Jovicic, N.
AU  - Mirković, Marija D.
AU  - Stanković, Dalibor M.
AU  - Mojovic, Z.
AU  - Bankovic, P.
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6061
AB  - (99)Technetium is one of the largest components of nuclear waste material. In aqueous solutions Tc-99 is present as the pertechnetate oxoanion, (TcO4-)-Tc-99, which is highly soluble and mobile in groundwater under oxidizing conditions, thus posing a major environmental concern. In this study, a series of organo-modified bentonite clay samples was tested as adsorbents for the removal of radioactive (TcO4-)-Tc-99 from aqueous solution at room temperature. The influence of the hexadecyl trimethylammonium (HDTMA)/bentonite ratio on the adsorption ability of the organobentonites was investigated. It was found that the adsorbent in which the exchangeable cations were only partially substituted with HDTMA showed very low affinity toward pertechnetate. On the other hand, the adsorbents in which the HDTMA loading exceeded the cation exchange capacity (CEC) value had high efficiency. The behavior of such adsorbents was best described by a Freundlich isotherm, while for the sample in which the HDTMA loading was equal to the CEC, the linear adsorption isotherm was the most appropriate. The difference in adsorption performance of several adsorbents was discussed from the point of view of the interlayer arrangement of the HDTMA. The kinetics of pertechnetate adsorption on HDTMA-bentonites was tested and analyzed using different surface reaction- and diffusion-based kinetic models. For all the investigated adsorbents, the most appropriate kinetic model was the pseudo-second-order kinetics model. The obtained adsorption capacities were and HDTMA-bentonites with HDTMA loadings exceeding CEC value should be regarded as very promising adsorbents for the remediation of Tc-99 polluted waters. (C) 2014 Elsevier B.V. All rights reserved.
T2  - Applied Clay Science
T1  - Removal of Tc-99(VII) by organo-modified bentonite
VL  - 95
SP  - 294
EP  - 302
DO  - 10.1016/j.clay.2014.04.027
ER  - 

@article{
author = "Milutinovic-Nikolic, A. and Maksin, Danijela D. and Jovic-Jovicic, N. and Mirković, Marija D. and Stanković, Dalibor M. and Mojovic, Z. and Bankovic, P.",
year = "2014",
abstract = "(99)Technetium is one of the largest components of nuclear waste material. In aqueous solutions Tc-99 is present as the pertechnetate oxoanion, (TcO4-)-Tc-99, which is highly soluble and mobile in groundwater under oxidizing conditions, thus posing a major environmental concern. In this study, a series of organo-modified bentonite clay samples was tested as adsorbents for the removal of radioactive (TcO4-)-Tc-99 from aqueous solution at room temperature. The influence of the hexadecyl trimethylammonium (HDTMA)/bentonite ratio on the adsorption ability of the organobentonites was investigated. It was found that the adsorbent in which the exchangeable cations were only partially substituted with HDTMA showed very low affinity toward pertechnetate. On the other hand, the adsorbents in which the HDTMA loading exceeded the cation exchange capacity (CEC) value had high efficiency. The behavior of such adsorbents was best described by a Freundlich isotherm, while for the sample in which the HDTMA loading was equal to the CEC, the linear adsorption isotherm was the most appropriate. The difference in adsorption performance of several adsorbents was discussed from the point of view of the interlayer arrangement of the HDTMA. The kinetics of pertechnetate adsorption on HDTMA-bentonites was tested and analyzed using different surface reaction- and diffusion-based kinetic models. For all the investigated adsorbents, the most appropriate kinetic model was the pseudo-second-order kinetics model. The obtained adsorption capacities were and HDTMA-bentonites with HDTMA loadings exceeding CEC value should be regarded as very promising adsorbents for the remediation of Tc-99 polluted waters. (C) 2014 Elsevier B.V. All rights reserved.",
journal = "Applied Clay Science",
title = "Removal of Tc-99(VII) by organo-modified bentonite",
volume = "95",
pages = "294-302",
doi = "10.1016/j.clay.2014.04.027"
}

Milutinovic-Nikolic, A., Maksin, D. D., Jovic-Jovicic, N., Mirković, M. D., Stanković, D. M., Mojovic, Z.,& Bankovic, P.. (2014). Removal of Tc-99(VII) by organo-modified bentonite. in Applied Clay Science, 95, 294-302.
https://doi.org/10.1016/j.clay.2014.04.027

Milutinovic-Nikolic A, Maksin DD, Jovic-Jovicic N, Mirković MD, Stanković DM, Mojovic Z, Bankovic P. Removal of Tc-99(VII) by organo-modified bentonite. in Applied Clay Science. 2014;95:294-302.
doi:10.1016/j.clay.2014.04.027 .

Milutinovic-Nikolic, A., Maksin, Danijela D., Jovic-Jovicic, N., Mirković, Marija D., Stanković, Dalibor M., Mojovic, Z., Bankovic, P., "Removal of Tc-99(VII) by organo-modified bentonite" in Applied Clay Science, 95 (2014):294-302,
https://doi.org/10.1016/j.clay.2014.04.027 . .

TY  - JOUR
AU  - Bankovic, P.
AU  - Milutinovic-Nikolic, A.
AU  - Mojovic, Z.
AU  - Jovic-Jovicic, N.
AU  - Perović, Marija M.
AU  - Spasojević, Vojislav
AU  - Jovanović, Dragana J.
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5162
AB  - Pillared clays (PILCs) based on bentonite clay from Bogovina (Serbia) were obtained using Al3+ and Fe3+ pillaring cations in different ratios. Thorough characterization of the starting material and PILCs was performed for better understanding of the catalytic activity that they had exibited in the catalytic wet peroxide oxidation (CWPO) of organic pollutants in water. The characterization consisted of the following techniques: XRD, XRD of oriented samples (swelling test), Greene-Kelley test (smectite type determination), TGA/DTA followed by XRD analysis of samples heated at characteristic temperatures, elemental analysis using ICP-OES and microwave digestion. FTIR, DR UV-Vis, Mossbauer spectroscopy, nitrogen physisorption at -196 degrees C and SEM imaging. Smectite in admixture with quartz was identified, together with impurities like feldspar, illite, chlorite and X-ray amorphous matter. Smectite mineral was dominantly of the beidellite type. Pillaring led to changes in the d(001) smectite basal spacing and stabilization of the smectite structure. Increasing Fe3+ content of the pillaring solutions resulted in the increased incorporation of iron into the PILCs as isolated octahedrally coordinated Fe3+ cations, smaller and bigger oligonuclear octahedrally coordinated Fe3+ species and octahedrally coordinated Fe3+ particles. The structure of incorporated pillars was similar to that of naturally occurring minerals akageneite and lepidocrocite. Micro- and mesoporosity were improved due to pillaring and the layered smectite structure was retained. (c) 2012 Elsevier Inc. All rights reserved.
T2  - Microporous and Mesoporous Materials
T1  - Synthesis and characterization of bentonites rich in beidellite with incorporated Al or Al-Fe oxide pillars
VL  - 165
SP  - 247
EP  - 256
DO  - 10.1016/j.micromeso.2012.08.029
ER  - 

@article{
author = "Bankovic, P. and Milutinovic-Nikolic, A. and Mojovic, Z. and Jovic-Jovicic, N. and Perović, Marija M. and Spasojević, Vojislav and Jovanović, Dragana J.",
year = "2013",
abstract = "Pillared clays (PILCs) based on bentonite clay from Bogovina (Serbia) were obtained using Al3+ and Fe3+ pillaring cations in different ratios. Thorough characterization of the starting material and PILCs was performed for better understanding of the catalytic activity that they had exibited in the catalytic wet peroxide oxidation (CWPO) of organic pollutants in water. The characterization consisted of the following techniques: XRD, XRD of oriented samples (swelling test), Greene-Kelley test (smectite type determination), TGA/DTA followed by XRD analysis of samples heated at characteristic temperatures, elemental analysis using ICP-OES and microwave digestion. FTIR, DR UV-Vis, Mossbauer spectroscopy, nitrogen physisorption at -196 degrees C and SEM imaging. Smectite in admixture with quartz was identified, together with impurities like feldspar, illite, chlorite and X-ray amorphous matter. Smectite mineral was dominantly of the beidellite type. Pillaring led to changes in the d(001) smectite basal spacing and stabilization of the smectite structure. Increasing Fe3+ content of the pillaring solutions resulted in the increased incorporation of iron into the PILCs as isolated octahedrally coordinated Fe3+ cations, smaller and bigger oligonuclear octahedrally coordinated Fe3+ species and octahedrally coordinated Fe3+ particles. The structure of incorporated pillars was similar to that of naturally occurring minerals akageneite and lepidocrocite. Micro- and mesoporosity were improved due to pillaring and the layered smectite structure was retained. (c) 2012 Elsevier Inc. All rights reserved.",
journal = "Microporous and Mesoporous Materials",
title = "Synthesis and characterization of bentonites rich in beidellite with incorporated Al or Al-Fe oxide pillars",
volume = "165",
pages = "247-256",
doi = "10.1016/j.micromeso.2012.08.029"
}

Bankovic, P., Milutinovic-Nikolic, A., Mojovic, Z., Jovic-Jovicic, N., Perović, M. M., Spasojević, V.,& Jovanović, D. J.. (2013). Synthesis and characterization of bentonites rich in beidellite with incorporated Al or Al-Fe oxide pillars. in Microporous and Mesoporous Materials, 165, 247-256.
https://doi.org/10.1016/j.micromeso.2012.08.029

Bankovic P, Milutinovic-Nikolic A, Mojovic Z, Jovic-Jovicic N, Perović MM, Spasojević V, Jovanović DJ. Synthesis and characterization of bentonites rich in beidellite with incorporated Al or Al-Fe oxide pillars. in Microporous and Mesoporous Materials. 2013;165:247-256.
doi:10.1016/j.micromeso.2012.08.029 .

Bankovic, P., Milutinovic-Nikolic, A., Mojovic, Z., Jovic-Jovicic, N., Perović, Marija M., Spasojević, Vojislav, Jovanović, Dragana J., "Synthesis and characterization of bentonites rich in beidellite with incorporated Al or Al-Fe oxide pillars" in Microporous and Mesoporous Materials, 165 (2013):247-256,
https://doi.org/10.1016/j.micromeso.2012.08.029 . .