TY  - CHAP
AU  - Krstić, Jugoslav
AU  - Mojović, Zorica
AU  - Rabi, A.A.
AU  - Lončarević, Davor
AU  - Vukelić, Nikola
AU  - Jovanović, D.
PY  - 2011
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/931
AB  - Technological development brought a number of advantages and conveniences to the modern life, but also brought many problems, environment pollution above all. Although a number of methods for water refining are already developed, there is still a demand to find a more efficient, cheaper and ecologically more acceptable sorbents. Possibility of using bentonite as naturally occurring material for methylene blue (MB) removal from its aqueous solutions was investigated in this paper. Characterization of starting material has been conducted by chemical analysis, XRD, particle size analysis, and N2 physisorption at -196C. The influence of the acidity of the initial MB solution on bentonite sorption characteristic was examined. Equilibrium sorption isotherms were determined. It was shown that with increase of pH and temperature the amount of sorbed MB increases.
PB  - Springer, New York
T2  - Survival and Sustainability. Environmental Earth Sciences.
T1  - Adsorption of methylene blue from aqueous solution onto bentonite
SP  - 1097
SP  - 1097
EP  - 1106
EP  - 1106
DO  - 10.1007/978-3-540-95991-5_103
ER  - 

@inbook{
author = "Krstić, Jugoslav and Mojović, Zorica and Rabi, A.A. and Lončarević, Davor and Vukelić, Nikola and Jovanović, D.",
year = "2011",
abstract = "Technological development brought a number of advantages and conveniences to the modern life, but also brought many problems, environment pollution above all. Although a number of methods for water refining are already developed, there is still a demand to find a more efficient, cheaper and ecologically more acceptable sorbents. Possibility of using bentonite as naturally occurring material for methylene blue (MB) removal from its aqueous solutions was investigated in this paper. Characterization of starting material has been conducted by chemical analysis, XRD, particle size analysis, and N2 physisorption at -196C. The influence of the acidity of the initial MB solution on bentonite sorption characteristic was examined. Equilibrium sorption isotherms were determined. It was shown that with increase of pH and temperature the amount of sorbed MB increases.",
publisher = "Springer, New York",
journal = "Survival and Sustainability. Environmental Earth Sciences.",
booktitle = "Adsorption of methylene blue from aqueous solution onto bentonite",
pages = "1097-1097-1106-1106",
doi = "10.1007/978-3-540-95991-5_103"
}

Krstić, J., Mojović, Z., Rabi, A.A., Lončarević, D., Vukelić, N.,& Jovanović, D.. (2011). Adsorption of methylene blue from aqueous solution onto bentonite. in Survival and Sustainability. Environmental Earth Sciences.
Springer, New York., 1097-1106.
https://doi.org/10.1007/978-3-540-95991-5_103

Krstić J, Mojović Z, Rabi A, Lončarević D, Vukelić N, Jovanović D. Adsorption of methylene blue from aqueous solution onto bentonite. in Survival and Sustainability. Environmental Earth Sciences.. 2011;:1097-1106.
doi:10.1007/978-3-540-95991-5_103 .

Krstić, Jugoslav, Mojović, Zorica, Rabi, A.A., Lončarević, Davor, Vukelić, Nikola, Jovanović, D., "Adsorption of methylene blue from aqueous solution onto bentonite" in Survival and Sustainability. Environmental Earth Sciences. (2011):1097-1106,
https://doi.org/10.1007/978-3-540-95991-5_103 . .

TY  - JOUR
AU  - Stanković, Miroslav
AU  - Gabrovska, Margarita
AU  - Krstić, Jugoslav
AU  - Tzvetkov, P.
AU  - Shopska, M.
AU  - Tsacheva, T.
AU  - Banković, Predrag
AU  - Edreva-Kardjieva, R.
AU  - Jovanović, D.
PY  - 2009
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/593
AB  - Silver modified Mg-Ni/diatomite materials with ratios of SiO2/Ni = 1.07 and Mg/Ni = 0.1, differing in Ag content (Ag/Ni = 0.025 and 0.1) were prepared by the precipitation-deposition method. The effects of silver presence and content on the structure, morphology, texture and H2-adsorption capacity of the obtained precursors were studied by X-ray diffraction, scanning electron microscopy, Hg-porosimetry and H2-chemisorption techniques. The catalytic performance of the corresponding catalysts in the soybean oil hydrogenation was investigated. The increase of the silver loading resulted in the development of macroporosity and increase in the total sample porosity. The decrease of both H2-adsorption capacity and hydrogenation activity are related to the metallic silver covering and blocking effects on the Ni2+ species, thus hampering the access of hydrogen. The decrease of hydrogenation activity and favorable limiting of cis-trans isomerization on the silver modified catalyst are explained by Horiuti-Polanyi mechanism based on the assumption that hydrogenation and isomerization proceed at the same active metallic nickel sites via half-hydrogenated intermediates. It was shown that the adjustment of the catalyst composition by changing the content of silver modifier offers the possibility to control the total amount of solid fat content, stearic acid and detrimental trans fatty acids in the hydrogenated derivatives. The catalyst with higher silver content is proposed as a promising candidate for selective edible oil hydrogenation catalyst.
PB  - Elsevier
T2  - Journal of Molecular Catalysis A: Chemical
T1  - Effect of silver modification on structure and catalytic performance of Ni-Mg/diatomite catalysts for edible oil hydrogenation
VL  - 297
IS  - 1-2
SP  - 54
EP  - 62
DO  - 10.1016/j.molcata.2008.09.004
ER  - 

@article{
author = "Stanković, Miroslav and Gabrovska, Margarita and Krstić, Jugoslav and Tzvetkov, P. and Shopska, M. and Tsacheva, T. and Banković, Predrag and Edreva-Kardjieva, R. and Jovanović, D.",
year = "2009",
abstract = "Silver modified Mg-Ni/diatomite materials with ratios of SiO2/Ni = 1.07 and Mg/Ni = 0.1, differing in Ag content (Ag/Ni = 0.025 and 0.1) were prepared by the precipitation-deposition method. The effects of silver presence and content on the structure, morphology, texture and H2-adsorption capacity of the obtained precursors were studied by X-ray diffraction, scanning electron microscopy, Hg-porosimetry and H2-chemisorption techniques. The catalytic performance of the corresponding catalysts in the soybean oil hydrogenation was investigated. The increase of the silver loading resulted in the development of macroporosity and increase in the total sample porosity. The decrease of both H2-adsorption capacity and hydrogenation activity are related to the metallic silver covering and blocking effects on the Ni2+ species, thus hampering the access of hydrogen. The decrease of hydrogenation activity and favorable limiting of cis-trans isomerization on the silver modified catalyst are explained by Horiuti-Polanyi mechanism based on the assumption that hydrogenation and isomerization proceed at the same active metallic nickel sites via half-hydrogenated intermediates. It was shown that the adjustment of the catalyst composition by changing the content of silver modifier offers the possibility to control the total amount of solid fat content, stearic acid and detrimental trans fatty acids in the hydrogenated derivatives. The catalyst with higher silver content is proposed as a promising candidate for selective edible oil hydrogenation catalyst.",
publisher = "Elsevier",
journal = "Journal of Molecular Catalysis A: Chemical",
title = "Effect of silver modification on structure and catalytic performance of Ni-Mg/diatomite catalysts for edible oil hydrogenation",
volume = "297",
number = "1-2",
pages = "54-62",
doi = "10.1016/j.molcata.2008.09.004"
}

Stanković, M., Gabrovska, M., Krstić, J., Tzvetkov, P., Shopska, M., Tsacheva, T., Banković, P., Edreva-Kardjieva, R.,& Jovanović, D.. (2009). Effect of silver modification on structure and catalytic performance of Ni-Mg/diatomite catalysts for edible oil hydrogenation. in Journal of Molecular Catalysis A: Chemical
Elsevier., 297(1-2), 54-62.
https://doi.org/10.1016/j.molcata.2008.09.004

Stanković M, Gabrovska M, Krstić J, Tzvetkov P, Shopska M, Tsacheva T, Banković P, Edreva-Kardjieva R, Jovanović D. Effect of silver modification on structure and catalytic performance of Ni-Mg/diatomite catalysts for edible oil hydrogenation. in Journal of Molecular Catalysis A: Chemical. 2009;297(1-2):54-62.
doi:10.1016/j.molcata.2008.09.004 .

Stanković, Miroslav, Gabrovska, Margarita, Krstić, Jugoslav, Tzvetkov, P., Shopska, M., Tsacheva, T., Banković, Predrag, Edreva-Kardjieva, R., Jovanović, D., "Effect of silver modification on structure and catalytic performance of Ni-Mg/diatomite catalysts for edible oil hydrogenation" in Journal of Molecular Catalysis A: Chemical, 297, no. 1-2 (2009):54-62,
https://doi.org/10.1016/j.molcata.2008.09.004 . .

TY  - CONF
AU  - Gabrovska, Margarita
AU  - Nikolova, Dimitrinka
AU  - Krstić, Jugoslav
AU  - Stanković, Miroslav
AU  - Stefanov, P.
AU  - Edreva-Kardjieva, R.
AU  - Jovanović, D.
PY  - 2009
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/583
AB  - Two series of silver modified Ni-Mg materials were synthesized by precipitation-deposition on SiO2 support derived from two silica sources: diatomite activated at 800°C (Series a; Mg/Ni = 0.1 and SiO 2/Ni = 1.07) and synthetic water glass (Series b; Mg/Ni = 0.1 and SiO2/Ni = 1.15). The modification with silver was made at three molar Ag/Ni ratios, namely 0.0025, 0.025, and 0.1. The effects of the source of the silica support and the silver presence and content on the nickel state in the silver modified reduced-passivated NiMg/SiO2 precursors of the vegetable oil hydrogenation catalyst were established by X-ray diffraction and X-ray photoelectron spectroscopy techniques. The passivation procedure was applied in order to protect the metallic nickel particles from further oxidation. The crystallization of the formed nickel hydrosilicate phases depends on the source of the silica support, more expressed in the diatomite supported samples. It was shown that the silver modification of the NiMg/SiO2 precursors enhances the reduction of the nickel hydrosilicates accompanied by formation of relatively smaller metallic nickel particles, more pronounced in the water glass supported precursors. The increase of the silver content in the water glass deposited samples is responsible for the metallic nickel dispersion increase. The higher content of the Ni0 particles on the surface of the diatomite deposited samples is in accordance with the higher stability of the larger metallic nickel crystallites to oxidation during the passivation step. On contrary, higher dispersed Ni0 particles on the surface of the water glass supported samples are more susceptible to the oxida
PB  - Maik Nauka/Interperiodica/Springer, New York
C3  - Russian Journal of Physical Chemistry A
T1  - The state of nickel in the silver modified NiMg/SiO2 vegetable oil hydrogenation catalysts
VL  - 83
IS  - 9
SP  - 1461
EP  - 1467
DO  - 10.1134/S0036024409090088
ER  - 

@conference{
author = "Gabrovska, Margarita and Nikolova, Dimitrinka and Krstić, Jugoslav and Stanković, Miroslav and Stefanov, P. and Edreva-Kardjieva, R. and Jovanović, D.",
year = "2009",
abstract = "Two series of silver modified Ni-Mg materials were synthesized by precipitation-deposition on SiO2 support derived from two silica sources: diatomite activated at 800°C (Series a; Mg/Ni = 0.1 and SiO 2/Ni = 1.07) and synthetic water glass (Series b; Mg/Ni = 0.1 and SiO2/Ni = 1.15). The modification with silver was made at three molar Ag/Ni ratios, namely 0.0025, 0.025, and 0.1. The effects of the source of the silica support and the silver presence and content on the nickel state in the silver modified reduced-passivated NiMg/SiO2 precursors of the vegetable oil hydrogenation catalyst were established by X-ray diffraction and X-ray photoelectron spectroscopy techniques. The passivation procedure was applied in order to protect the metallic nickel particles from further oxidation. The crystallization of the formed nickel hydrosilicate phases depends on the source of the silica support, more expressed in the diatomite supported samples. It was shown that the silver modification of the NiMg/SiO2 precursors enhances the reduction of the nickel hydrosilicates accompanied by formation of relatively smaller metallic nickel particles, more pronounced in the water glass supported precursors. The increase of the silver content in the water glass deposited samples is responsible for the metallic nickel dispersion increase. The higher content of the Ni0 particles on the surface of the diatomite deposited samples is in accordance with the higher stability of the larger metallic nickel crystallites to oxidation during the passivation step. On contrary, higher dispersed Ni0 particles on the surface of the water glass supported samples are more susceptible to the oxida",
publisher = "Maik Nauka/Interperiodica/Springer, New York",
journal = "Russian Journal of Physical Chemistry A",
title = "The state of nickel in the silver modified NiMg/SiO2 vegetable oil hydrogenation catalysts",
volume = "83",
number = "9",
pages = "1461-1467",
doi = "10.1134/S0036024409090088"
}

Gabrovska, M., Nikolova, D., Krstić, J., Stanković, M., Stefanov, P., Edreva-Kardjieva, R.,& Jovanović, D.. (2009). The state of nickel in the silver modified NiMg/SiO2 vegetable oil hydrogenation catalysts. in Russian Journal of Physical Chemistry A
Maik Nauka/Interperiodica/Springer, New York., 83(9), 1461-1467.
https://doi.org/10.1134/S0036024409090088

Gabrovska M, Nikolova D, Krstić J, Stanković M, Stefanov P, Edreva-Kardjieva R, Jovanović D. The state of nickel in the silver modified NiMg/SiO2 vegetable oil hydrogenation catalysts. in Russian Journal of Physical Chemistry A. 2009;83(9):1461-1467.
doi:10.1134/S0036024409090088 .

Gabrovska, Margarita, Nikolova, Dimitrinka, Krstić, Jugoslav, Stanković, Miroslav, Stefanov, P., Edreva-Kardjieva, R., Jovanović, D., "The state of nickel in the silver modified NiMg/SiO2 vegetable oil hydrogenation catalysts" in Russian Journal of Physical Chemistry A, 83, no. 9 (2009):1461-1467,
https://doi.org/10.1134/S0036024409090088 . .

TY  - JOUR
AU  - Lukić, I.
AU  - Krstić, Jugoslav
AU  - Jovanović, D.
AU  - Skala, Dejan
PY  - 2009
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/605
AB  - The new type of catalyst for fatty acid methyl esters (FAME or biodiesel) synthesis with K2CO3 as active component on alumina/silica support was synthesized using sol-gel method. Corresponding catalyst (xerogel) was prepared by 12 h drying the wet gel in air at 300 °C, 600 °C or 1000 °C at atmospheric pressure. The catalysts activity in the methanolysis of sunflower oil was compared to the activity of the pure K2CO3. The effects of various reaction variables on the yield of FAME were investigated. It was found that the temperature of 120 °C and methanol to oil molar ratio of 15:1, are optimal conditions for FAME synthesis with synthesized catalyst. Repeated use of same amount of catalyst indicated that effect of potassium leaching obviously existed leading to decrease of catalyst activity.
PB  - Elsevier Sci Ltd, Oxford
T2  - Bioresource Technology
T1  - Alumina/silica supported K2CO3 as a catalyst for biodiesel synthesis from sunflower oil
VL  - 100
IS  - 20
SP  - 4690
EP  - 4696
DO  - 10.1016/j.biortech.2009.04.057
ER  - 

@article{
author = "Lukić, I. and Krstić, Jugoslav and Jovanović, D. and Skala, Dejan",
year = "2009",
abstract = "The new type of catalyst for fatty acid methyl esters (FAME or biodiesel) synthesis with K2CO3 as active component on alumina/silica support was synthesized using sol-gel method. Corresponding catalyst (xerogel) was prepared by 12 h drying the wet gel in air at 300 °C, 600 °C or 1000 °C at atmospheric pressure. The catalysts activity in the methanolysis of sunflower oil was compared to the activity of the pure K2CO3. The effects of various reaction variables on the yield of FAME were investigated. It was found that the temperature of 120 °C and methanol to oil molar ratio of 15:1, are optimal conditions for FAME synthesis with synthesized catalyst. Repeated use of same amount of catalyst indicated that effect of potassium leaching obviously existed leading to decrease of catalyst activity.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Bioresource Technology",
title = "Alumina/silica supported K2CO3 as a catalyst for biodiesel synthesis from sunflower oil",
volume = "100",
number = "20",
pages = "4690-4696",
doi = "10.1016/j.biortech.2009.04.057"
}

Lukić, I., Krstić, J., Jovanović, D.,& Skala, D.. (2009). Alumina/silica supported K2CO3 as a catalyst for biodiesel synthesis from sunflower oil. in Bioresource Technology
Elsevier Sci Ltd, Oxford., 100(20), 4690-4696.
https://doi.org/10.1016/j.biortech.2009.04.057

Lukić I, Krstić J, Jovanović D, Skala D. Alumina/silica supported K2CO3 as a catalyst for biodiesel synthesis from sunflower oil. in Bioresource Technology. 2009;100(20):4690-4696.
doi:10.1016/j.biortech.2009.04.057 .

Lukić, I., Krstić, Jugoslav, Jovanović, D., Skala, Dejan, "Alumina/silica supported K2CO3 as a catalyst for biodiesel synthesis from sunflower oil" in Bioresource Technology, 100, no. 20 (2009):4690-4696,
https://doi.org/10.1016/j.biortech.2009.04.057 . .

TY  - JOUR
AU  - Skala, Dejan
AU  - Orlović, Aleksandar
AU  - Marković, Bojana
AU  - Terlecki-Baričević, Ana V.
AU  - Jovanović, D.
PY  - 2002
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/83
AB  - The performed investigations were directed toward the analysis of the performance and activity of the fresh and regenerated Cyanamid HDS 20C catalyst in a laboratory batch reactor (2 dm3) for the HDS of the diesel fraction (light gas oil, LGO). Testing of the regenerated catalyst was performed with light gas oil (LGO) of different characteristics. The determined values of the reaction rate constant were compared to some published data in the literature for the HDS of specific sulfur compounds as well as the values of the activation energy. The rates of deactivation of the fresh and regenerated catalyst actually existed compared to some other results recently published in the literature. However, such an observed differences were not sufficient to derive a relation which could be used for the determination of the rate of catalyst deactivation.
PB  - Association of the Chemical Engineers of Serbia
T2  - Chemical Industry and Chemical Engineering Quarterly / CICEQ
T1  - Hydrodesulfurization of light gas oil - kinetic determination in a batch reactor [Hidrodesulfurizacija lakog gasnog ulja - ispitivanje kinetike HDS u šaržnom reaktoru]
VL  - 8
IS  - 4
SP  - 529
EP  - 532
UR  - https://hdl.handle.net/21.15107/rcub_cer_83
ER  - 

@article{
author = "Skala, Dejan and Orlović, Aleksandar and Marković, Bojana and Terlecki-Baričević, Ana V. and Jovanović, D.",
year = "2002",
abstract = "The performed investigations were directed toward the analysis of the performance and activity of the fresh and regenerated Cyanamid HDS 20C catalyst in a laboratory batch reactor (2 dm3) for the HDS of the diesel fraction (light gas oil, LGO). Testing of the regenerated catalyst was performed with light gas oil (LGO) of different characteristics. The determined values of the reaction rate constant were compared to some published data in the literature for the HDS of specific sulfur compounds as well as the values of the activation energy. The rates of deactivation of the fresh and regenerated catalyst actually existed compared to some other results recently published in the literature. However, such an observed differences were not sufficient to derive a relation which could be used for the determination of the rate of catalyst deactivation.",
publisher = "Association of the Chemical Engineers of Serbia",
journal = "Chemical Industry and Chemical Engineering Quarterly / CICEQ",
title = "Hydrodesulfurization of light gas oil - kinetic determination in a batch reactor [Hidrodesulfurizacija lakog gasnog ulja - ispitivanje kinetike HDS u šaržnom reaktoru]",
volume = "8",
number = "4",
pages = "529-532",
url = "https://hdl.handle.net/21.15107/rcub_cer_83"
}

Skala, D., Orlović, A., Marković, B., Terlecki-Baričević, A. V.,& Jovanović, D.. (2002). Hydrodesulfurization of light gas oil - kinetic determination in a batch reactor [Hidrodesulfurizacija lakog gasnog ulja - ispitivanje kinetike HDS u šaržnom reaktoru]. in Chemical Industry and Chemical Engineering Quarterly / CICEQ
Association of the Chemical Engineers of Serbia., 8(4), 529-532.
https://hdl.handle.net/21.15107/rcub_cer_83

Skala D, Orlović A, Marković B, Terlecki-Baričević AV, Jovanović D. Hydrodesulfurization of light gas oil - kinetic determination in a batch reactor [Hidrodesulfurizacija lakog gasnog ulja - ispitivanje kinetike HDS u šaržnom reaktoru]. in Chemical Industry and Chemical Engineering Quarterly / CICEQ. 2002;8(4):529-532.
https://hdl.handle.net/21.15107/rcub_cer_83 .

Skala, Dejan, Orlović, Aleksandar, Marković, Bojana, Terlecki-Baričević, Ana V., Jovanović, D., "Hydrodesulfurization of light gas oil - kinetic determination in a batch reactor [Hidrodesulfurizacija lakog gasnog ulja - ispitivanje kinetike HDS u šaržnom reaktoru]" in Chemical Industry and Chemical Engineering Quarterly / CICEQ, 8, no. 4 (2002):529-532,
https://hdl.handle.net/21.15107/rcub_cer_83 .