TY  - JOUR
AU  - Pavlović, Jelena
AU  - Popova, M.
AU  - Mihalyi, R. M.
AU  - Mazaj, Matjaz
AU  - Mali, Gregor
AU  - Kovač, Janez
AU  - Lazarova, H.
AU  - Rajić, Nevenka
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4157
AB  - Catalysts based on natural zeolite - clinoptilolite loaded with either SnO2 (TOHCLI) or sulfated SnO2 (STOHCLI) were prepared and tested in the esterification of levulinic acid (LA) with octanol or ethanol. The Sn content in TOHCLI and STOHCLI varied from 4.5 to 12.3 wt.%. The catalysts were characterized by powder X-ray diffraction method, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, thermal analysis, X-ray photoelectron spectroscopy, NZ physisorption at - 196 degrees C, (27)A1 and Si-29 MAS NMR solid state spectroscopy and FTIR spectroscopy for analysis of acidic centers. A high conversion rate of LA into octyl- (OLA) or ethyl levulinate (ELA) was obtained for both TOHCLI and STOHCLI. TOHCLI showed a high activity in the conversion of LA into OLA (55%) and a moderate activity in the conversion to ELA (22%). STOHCLI led to a total conversion of LA to OLA and ELA due to the presence of a high amount of Bronsted and Lewis acid sites in the catalysts. The catalytic activity decreased to 86% for OLA and to 66% for ELA after next five cycles. Lower catalytic activity in the repeated cycles during ELA formation was explained by pore blockage due to coke formation.
PB  - Elsevier B.V.
T2  - Microporous and Mesoporous Materials
T1  - Catalytic activity of SnO2- and SO4 /SnO2-containing clinoptilolite in the esterification of levulinic acid
EP  - 18
SP  - 10
VL  - 279
DO  - 10.1016/j.micromeso.2018.12.009
ER  - 

@article{
author = "Pavlović, Jelena and Popova, M. and Mihalyi, R. M. and Mazaj, Matjaz and Mali, Gregor and Kovač, Janez and Lazarova, H. and Rajić, Nevenka",
year = "2019",
abstract = "Catalysts based on natural zeolite - clinoptilolite loaded with either SnO2 (TOHCLI) or sulfated SnO2 (STOHCLI) were prepared and tested in the esterification of levulinic acid (LA) with octanol or ethanol. The Sn content in TOHCLI and STOHCLI varied from 4.5 to 12.3 wt.%. The catalysts were characterized by powder X-ray diffraction method, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, thermal analysis, X-ray photoelectron spectroscopy, NZ physisorption at - 196 degrees C, (27)A1 and Si-29 MAS NMR solid state spectroscopy and FTIR spectroscopy for analysis of acidic centers. A high conversion rate of LA into octyl- (OLA) or ethyl levulinate (ELA) was obtained for both TOHCLI and STOHCLI. TOHCLI showed a high activity in the conversion of LA into OLA (55%) and a moderate activity in the conversion to ELA (22%). STOHCLI led to a total conversion of LA to OLA and ELA due to the presence of a high amount of Bronsted and Lewis acid sites in the catalysts. The catalytic activity decreased to 86% for OLA and to 66% for ELA after next five cycles. Lower catalytic activity in the repeated cycles during ELA formation was explained by pore blockage due to coke formation.",
publisher = "Elsevier B.V.",
journal = "Microporous and Mesoporous Materials",
title = "Catalytic activity of SnO2- and SO4 /SnO2-containing clinoptilolite in the esterification of levulinic acid",
pages = "18-10",
volume = "279",
doi = "10.1016/j.micromeso.2018.12.009"
}

Pavlović, J., Popova, M., Mihalyi, R. M., Mazaj, M., Mali, G., Kovač, J., Lazarova, H.,& Rajić, N.. (2019). Catalytic activity of SnO2- and SO4 /SnO2-containing clinoptilolite in the esterification of levulinic acid. in Microporous and Mesoporous Materials
Elsevier B.V.., 279, 10-18.
https://doi.org/10.1016/j.micromeso.2018.12.009

Pavlović J, Popova M, Mihalyi RM, Mazaj M, Mali G, Kovač J, Lazarova H, Rajić N. Catalytic activity of SnO2- and SO4 /SnO2-containing clinoptilolite in the esterification of levulinic acid. in Microporous and Mesoporous Materials. 2019;279:10-18.
doi:10.1016/j.micromeso.2018.12.009 .

Pavlović, Jelena, Popova, M., Mihalyi, R. M., Mazaj, Matjaz, Mali, Gregor, Kovač, Janez, Lazarova, H., Rajić, Nevenka, "Catalytic activity of SnO2- and SO4 /SnO2-containing clinoptilolite in the esterification of levulinic acid" in Microporous and Mesoporous Materials, 279 (2019):10-18,
https://doi.org/10.1016/j.micromeso.2018.12.009 . .

TY  - JOUR
AU  - Pavlović, Jelena
AU  - Popova, M.
AU  - Mihalyi, R. M.
AU  - Mazaj, Matjaz
AU  - Mali, Gregor
AU  - Kovač, Janez
AU  - Lazarova, H.
AU  - Rajić, Nevenka
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5042
AB  - Catalysts based on natural zeolite – clinoptilolite loaded with either SnO2 (TOHCLI) or sulfated SnO2 (STOHCLI) were prepared and tested in the esterification of levulinic acid (LA) with octanol or ethanol. The Sn content in TOHCLI and STOHCLI varied from 4.5 to 12.3 wt.%. The catalysts were characterized by powder X-ray diffraction method, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, thermal analysis, X-ray photoelectron spectroscopy, N2 physisorption at −196 °C, 27Al and 29Si MAS NMR solid state spectroscopy and FTIR spectroscopy for analysis of acidic centers. A high conversion rate of LA into octyl- (OLA) or ethyl levulinate (ELA) was obtained for both TOHCLI and STOHCLI. TOHCLI showed a high activity in the conversion of LA into OLA (55%) and a moderate activity in the conversion to ELA (22%). STOHCLI led to a total conversion of LA to OLA and ELA due to the presence of a high amount of Brønsted and Lewis acid sites in the catalysts. The catalytic activity decreased to 86% for OLA and to 66% for ELA after next five cycles. Lower catalytic activity in the repeated cycles during ELA formation was explained by pore blockage due to coke formation.
PB  - Elsevier B.V.
T2  - Microporous and Mesoporous Materials
T1  - Catalytic activity of SnO2- and SO4/SnO2-containing clinoptilolite in the esterification of levulinic acid
EP  - 18
SP  - 10
VL  - 279
DO  - 10.1016/j.micromeso.2018.12.009
ER  - 

@article{
author = "Pavlović, Jelena and Popova, M. and Mihalyi, R. M. and Mazaj, Matjaz and Mali, Gregor and Kovač, Janez and Lazarova, H. and Rajić, Nevenka",
year = "2019",
abstract = "Catalysts based on natural zeolite – clinoptilolite loaded with either SnO2 (TOHCLI) or sulfated SnO2 (STOHCLI) were prepared and tested in the esterification of levulinic acid (LA) with octanol or ethanol. The Sn content in TOHCLI and STOHCLI varied from 4.5 to 12.3 wt.%. The catalysts were characterized by powder X-ray diffraction method, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, thermal analysis, X-ray photoelectron spectroscopy, N2 physisorption at −196 °C, 27Al and 29Si MAS NMR solid state spectroscopy and FTIR spectroscopy for analysis of acidic centers. A high conversion rate of LA into octyl- (OLA) or ethyl levulinate (ELA) was obtained for both TOHCLI and STOHCLI. TOHCLI showed a high activity in the conversion of LA into OLA (55%) and a moderate activity in the conversion to ELA (22%). STOHCLI led to a total conversion of LA to OLA and ELA due to the presence of a high amount of Brønsted and Lewis acid sites in the catalysts. The catalytic activity decreased to 86% for OLA and to 66% for ELA after next five cycles. Lower catalytic activity in the repeated cycles during ELA formation was explained by pore blockage due to coke formation.",
publisher = "Elsevier B.V.",
journal = "Microporous and Mesoporous Materials",
title = "Catalytic activity of SnO2- and SO4/SnO2-containing clinoptilolite in the esterification of levulinic acid",
pages = "18-10",
volume = "279",
doi = "10.1016/j.micromeso.2018.12.009"
}

Pavlović, J., Popova, M., Mihalyi, R. M., Mazaj, M., Mali, G., Kovač, J., Lazarova, H.,& Rajić, N.. (2019). Catalytic activity of SnO2- and SO4/SnO2-containing clinoptilolite in the esterification of levulinic acid. in Microporous and Mesoporous Materials
Elsevier B.V.., 279, 10-18.
https://doi.org/10.1016/j.micromeso.2018.12.009

Pavlović J, Popova M, Mihalyi RM, Mazaj M, Mali G, Kovač J, Lazarova H, Rajić N. Catalytic activity of SnO2- and SO4/SnO2-containing clinoptilolite in the esterification of levulinic acid. in Microporous and Mesoporous Materials. 2019;279:10-18.
doi:10.1016/j.micromeso.2018.12.009 .

Pavlović, Jelena, Popova, M., Mihalyi, R. M., Mazaj, Matjaz, Mali, Gregor, Kovač, Janez, Lazarova, H., Rajić, Nevenka, "Catalytic activity of SnO2- and SO4/SnO2-containing clinoptilolite in the esterification of levulinic acid" in Microporous and Mesoporous Materials, 279 (2019):10-18,
https://doi.org/10.1016/j.micromeso.2018.12.009 . .

TY  - JOUR
AU  - Jevtić, Sanja
AU  - Arcon, Iztok
AU  - Recnik, Aleksander
AU  - Babić, Biljana M.
AU  - Mazaj, Matjaz
AU  - Pavlović, Jelena
AU  - Matijasević, Danka
AU  - Nikšić, Miomir
AU  - Rajić, Nevenka
PY  - 2014
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2662
AB  - Se(IV) and Se(VI) anions are the dominant species of Se existing in aqueous systems. In this study, the iron(III)-modified natural zeolitic tuff (Fe-CLI) from the Serbian deposit Zlatokop has been investigated as an adsorbent for the Se oxyanions. Fe-CLI shows adsorption activity for both Se(IV) and Se(VI) which decreases with increasing pH. The adsorption capacity of Fe-CLI is found to be higher for Se(IV) than for Se(VI). Kinetics data follow the pseudo-second-order model and the obtained parameters k indicate that the rates of adsorption and desorption are higher for Se(VI). Extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) analyses reveal that Se is bound at the zeolite surface forming not only the Se-O-Fe but also Se-O-Si bonds. The adsorption mechanism depends of the type of oxo ions. Samples of zeolitic tuff which contain Se were tested as soil supplements for the cultivation of Pleurotus ostreatus mushrooms. The fungus adsorbed the inorganic Se from zeolitic tuff transforming it to a more valuable organically bound form.
PB  - Elsevier, Amsterdam
T2  - Microporous and Mesoporous Materials
T1  - The iron(III)-modified natural zeolitic tuff as an adsorbent and carrier for selenium oxyanions
EP  - 100
SP  - 92
VL  - 197
DO  - 10.1016/j.micromeso.2014.06.008
ER  - 

@article{
author = "Jevtić, Sanja and Arcon, Iztok and Recnik, Aleksander and Babić, Biljana M. and Mazaj, Matjaz and Pavlović, Jelena and Matijasević, Danka and Nikšić, Miomir and Rajić, Nevenka",
year = "2014",
abstract = "Se(IV) and Se(VI) anions are the dominant species of Se existing in aqueous systems. In this study, the iron(III)-modified natural zeolitic tuff (Fe-CLI) from the Serbian deposit Zlatokop has been investigated as an adsorbent for the Se oxyanions. Fe-CLI shows adsorption activity for both Se(IV) and Se(VI) which decreases with increasing pH. The adsorption capacity of Fe-CLI is found to be higher for Se(IV) than for Se(VI). Kinetics data follow the pseudo-second-order model and the obtained parameters k indicate that the rates of adsorption and desorption are higher for Se(VI). Extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) analyses reveal that Se is bound at the zeolite surface forming not only the Se-O-Fe but also Se-O-Si bonds. The adsorption mechanism depends of the type of oxo ions. Samples of zeolitic tuff which contain Se were tested as soil supplements for the cultivation of Pleurotus ostreatus mushrooms. The fungus adsorbed the inorganic Se from zeolitic tuff transforming it to a more valuable organically bound form.",
publisher = "Elsevier, Amsterdam",
journal = "Microporous and Mesoporous Materials",
title = "The iron(III)-modified natural zeolitic tuff as an adsorbent and carrier for selenium oxyanions",
pages = "100-92",
volume = "197",
doi = "10.1016/j.micromeso.2014.06.008"
}

Jevtić, S., Arcon, I., Recnik, A., Babić, B. M., Mazaj, M., Pavlović, J., Matijasević, D., Nikšić, M.,& Rajić, N.. (2014). The iron(III)-modified natural zeolitic tuff as an adsorbent and carrier for selenium oxyanions. in Microporous and Mesoporous Materials
Elsevier, Amsterdam., 197, 92-100.
https://doi.org/10.1016/j.micromeso.2014.06.008

Jevtić S, Arcon I, Recnik A, Babić BM, Mazaj M, Pavlović J, Matijasević D, Nikšić M, Rajić N. The iron(III)-modified natural zeolitic tuff as an adsorbent and carrier for selenium oxyanions. in Microporous and Mesoporous Materials. 2014;197:92-100.
doi:10.1016/j.micromeso.2014.06.008 .

Jevtić, Sanja, Arcon, Iztok, Recnik, Aleksander, Babić, Biljana M., Mazaj, Matjaz, Pavlović, Jelena, Matijasević, Danka, Nikšić, Miomir, Rajić, Nevenka, "The iron(III)-modified natural zeolitic tuff as an adsorbent and carrier for selenium oxyanions" in Microporous and Mesoporous Materials, 197 (2014):92-100,
https://doi.org/10.1016/j.micromeso.2014.06.008 . .

TY  - JOUR
AU  - Stojaković, Đorđe
AU  - Hrenović, Jasna
AU  - Mazaj, Matjaz
AU  - Rajić, Nevenka
PY  - 2011
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1950
AB  - The Serbian natural zeolite is moderately effective in removing the zinc(II) ions from aqueous solutions. At 298 K the sorption capacity varies from 13 to 26% for the initial Zn(II) solution concentration of 100 and 600 mgZn dm(-3), respectively. The sorption isotherm at 298-338 K is best represented by the Langmuir model and the sorption kinetics by the pseudo-second-order model. The sorption involves a combination of film diffusion, intra-particle diffusion, and a chemical cation-exchange between the Na+ ions of clinoptilolite and Zn2+ ions. The sorption was found to be endothermic and spontaneous in the 298-338 K range. The exhausted sorbent can remove phosphate ions and it exhibits an excellent antibacterial activity towards Acinetobacter junii. By dehydration at about 500 degrees C it transforms to a ZnO-containing product featuring nano-sized wurtzite ZnO particles widespread over the clinoptilolite surface.
PB  - Elsevier, Amsterdam
T2  - Journal of Hazardous Materials
T1  - On the zinc sorption by the Serbian natural clinoptilolite and the disinfecting ability and phosphate affinity of the exhausted sorbent
EP  - 415
IS  - 1
SP  - 408
VL  - 185
DO  - 10.1016/j.jhazmat.2010.09.048
ER  - 

@article{
author = "Stojaković, Đorđe and Hrenović, Jasna and Mazaj, Matjaz and Rajić, Nevenka",
year = "2011",
abstract = "The Serbian natural zeolite is moderately effective in removing the zinc(II) ions from aqueous solutions. At 298 K the sorption capacity varies from 13 to 26% for the initial Zn(II) solution concentration of 100 and 600 mgZn dm(-3), respectively. The sorption isotherm at 298-338 K is best represented by the Langmuir model and the sorption kinetics by the pseudo-second-order model. The sorption involves a combination of film diffusion, intra-particle diffusion, and a chemical cation-exchange between the Na+ ions of clinoptilolite and Zn2+ ions. The sorption was found to be endothermic and spontaneous in the 298-338 K range. The exhausted sorbent can remove phosphate ions and it exhibits an excellent antibacterial activity towards Acinetobacter junii. By dehydration at about 500 degrees C it transforms to a ZnO-containing product featuring nano-sized wurtzite ZnO particles widespread over the clinoptilolite surface.",
publisher = "Elsevier, Amsterdam",
journal = "Journal of Hazardous Materials",
title = "On the zinc sorption by the Serbian natural clinoptilolite and the disinfecting ability and phosphate affinity of the exhausted sorbent",
pages = "415-408",
number = "1",
volume = "185",
doi = "10.1016/j.jhazmat.2010.09.048"
}

Stojaković, Đ., Hrenović, J., Mazaj, M.,& Rajić, N.. (2011). On the zinc sorption by the Serbian natural clinoptilolite and the disinfecting ability and phosphate affinity of the exhausted sorbent. in Journal of Hazardous Materials
Elsevier, Amsterdam., 185(1), 408-415.
https://doi.org/10.1016/j.jhazmat.2010.09.048

Stojaković Đ, Hrenović J, Mazaj M, Rajić N. On the zinc sorption by the Serbian natural clinoptilolite and the disinfecting ability and phosphate affinity of the exhausted sorbent. in Journal of Hazardous Materials. 2011;185(1):408-415.
doi:10.1016/j.jhazmat.2010.09.048 .

Stojaković, Đorđe, Hrenović, Jasna, Mazaj, Matjaz, Rajić, Nevenka, "On the zinc sorption by the Serbian natural clinoptilolite and the disinfecting ability and phosphate affinity of the exhausted sorbent" in Journal of Hazardous Materials, 185, no. 1 (2011):408-415,
https://doi.org/10.1016/j.jhazmat.2010.09.048 . .

TY  - JOUR
AU  - Rajić, Nevenka
AU  - Stojaković, Đorđe
AU  - Jovanović, Mina
AU  - Zabukovec-Logar, Nataša
AU  - Mazaj, Matjaz
AU  - Kaučič, Venčeslav
PY  - 2010
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1726
AB  - The natural zeolite tuff (clinoptilolite) from a Serbian deposit has been studied as adsorbent for Ni(II) ions from aqueous solutions. Its sorption capacity at 298K varies from 1.9mg Nig(-1) (for the initial solution concentration of 100mg Nidm(-3)) to 3.8mg Nig(-1) (for C-0 = 600mgNidm(-3)) and it increases 3 times at 338 K. The sorption is best described by the Sips isotherm model. The sorption kinetics follows the pseudo-second-order model, the activation energies being 7.44, 5.86, 6.62 and 6.63 kJ mol(-1) for C-0 = 100, 200, 300 and 400mg Nidm(-3), respectively. The sorption involves a film diffusion, an intra-particle diffusion, and a chemical cation-exchange between the Na+ ions of clinoptilolite and the Ni2+ ions. The sorption is endothermic (Delta H degrees being 37.9, 33.4, 30.0, 27.7 and 24.3 kJ mol(-1) for C-0 = 100, 200, 300, 400 and 600mg Nidm(-3), respectively) and spontaneous in the 298-338K temperature range. Thermal treatment of the Ni(II)-loaded clinoptilolite results in the formation of spherical nano-NiO particles of approx. 5 nm in diameter which are randomly dispersed in the clinoptilolite lattice.
PB  - Elsevier Science Bv, Amsterdam
T2  - Applied Surface Science
T1  - Removal of nickel(II) ions from aqueous solutions using the natural clinoptilolite and preparation of nano-NiO on the exhausted clinoptilolite
EP  - 1532
IS  - 5
SP  - 1524
VL  - 257
DO  - 10.1016/j.apsusc.2010.08.090
ER  - 

@article{
author = "Rajić, Nevenka and Stojaković, Đorđe and Jovanović, Mina and Zabukovec-Logar, Nataša and Mazaj, Matjaz and Kaučič, Venčeslav",
year = "2010",
abstract = "The natural zeolite tuff (clinoptilolite) from a Serbian deposit has been studied as adsorbent for Ni(II) ions from aqueous solutions. Its sorption capacity at 298K varies from 1.9mg Nig(-1) (for the initial solution concentration of 100mg Nidm(-3)) to 3.8mg Nig(-1) (for C-0 = 600mgNidm(-3)) and it increases 3 times at 338 K. The sorption is best described by the Sips isotherm model. The sorption kinetics follows the pseudo-second-order model, the activation energies being 7.44, 5.86, 6.62 and 6.63 kJ mol(-1) for C-0 = 100, 200, 300 and 400mg Nidm(-3), respectively. The sorption involves a film diffusion, an intra-particle diffusion, and a chemical cation-exchange between the Na+ ions of clinoptilolite and the Ni2+ ions. The sorption is endothermic (Delta H degrees being 37.9, 33.4, 30.0, 27.7 and 24.3 kJ mol(-1) for C-0 = 100, 200, 300, 400 and 600mg Nidm(-3), respectively) and spontaneous in the 298-338K temperature range. Thermal treatment of the Ni(II)-loaded clinoptilolite results in the formation of spherical nano-NiO particles of approx. 5 nm in diameter which are randomly dispersed in the clinoptilolite lattice.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Applied Surface Science",
title = "Removal of nickel(II) ions from aqueous solutions using the natural clinoptilolite and preparation of nano-NiO on the exhausted clinoptilolite",
pages = "1532-1524",
number = "5",
volume = "257",
doi = "10.1016/j.apsusc.2010.08.090"
}

Rajić, N., Stojaković, Đ., Jovanović, M., Zabukovec-Logar, N., Mazaj, M.,& Kaučič, V.. (2010). Removal of nickel(II) ions from aqueous solutions using the natural clinoptilolite and preparation of nano-NiO on the exhausted clinoptilolite. in Applied Surface Science
Elsevier Science Bv, Amsterdam., 257(5), 1524-1532.
https://doi.org/10.1016/j.apsusc.2010.08.090

Rajić N, Stojaković Đ, Jovanović M, Zabukovec-Logar N, Mazaj M, Kaučič V. Removal of nickel(II) ions from aqueous solutions using the natural clinoptilolite and preparation of nano-NiO on the exhausted clinoptilolite. in Applied Surface Science. 2010;257(5):1524-1532.
doi:10.1016/j.apsusc.2010.08.090 .

Rajić, Nevenka, Stojaković, Đorđe, Jovanović, Mina, Zabukovec-Logar, Nataša, Mazaj, Matjaz, Kaučič, Venčeslav, "Removal of nickel(II) ions from aqueous solutions using the natural clinoptilolite and preparation of nano-NiO on the exhausted clinoptilolite" in Applied Surface Science, 257, no. 5 (2010):1524-1532,
https://doi.org/10.1016/j.apsusc.2010.08.090 . .