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 . .