TY  - JOUR
AU  - Nježić, Zvonko
AU  - Kostić, Milan D.
AU  - Marić, Boško D.
AU  - Stamenković, Olivera
AU  - Šimurina, Olivera D.
AU  - Krstić, Jugoslav
AU  - Veljković, Vlada B.
PY  - 2023
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/5399
AB  - A low-cost, highly active CaO-based catalyst was prepared from waste filter cake (WFC) from a sugar beet processing factory by calcination in air at 900 °C for 2 h, referred to as the calcined filter cake (CFC). It was used to catalyze the rapeseed oil transesterification with methanol under mild reaction conditions (methanol-to-oil molar ratio of 9:1, catalyst loading of 4–10 %, and reaction temperature of 40–60 °C). Rapeseed oil was characterized regarding the physicochemical properties and fatty acid profile. Low free fatty acid content (about 2.0 mg KOH/g) allowed the direct use of the base CFC catalyst for rapeseed oil transesterification. Rapeseed oil has more unsaturated fatty acids (about 93 %), with oleic acid as the most abundant, than saturated fatty acids (about 7 %). A simplified model combining the changing mechanism of the reaction and the triacylglycerols mass transfer limitation successfully describes the kinetics of transesterification. A good agreement between the model and the experiment was proved by the mean relative percentage deviation for the conversion degree of only ± 7.43 % (based on 42 data). The apparent reaction rate constant follows the Arrhenius equation with the activation energy of 51.9 kJ mol−1. The FAME content higher than 96.5 % can be obtained in wide ranges of the catalyst amount (4–10 %) and the reaction time (about 45–70 min). The following conditions were optimum: the reaction temperature of 59.2 °C, the catalyst loading of 9.1 % (based on the oil weight), and the reaction time of 47 min.
PB  - Elsevier
T2  - Fuel
T1  - Kinetics and optimization of biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing plant
VL  - 334
SP  - 126581
DO  - 10.1016/j.fuel.2022.126581
ER  - 

@article{
author = "Nježić, Zvonko and Kostić, Milan D. and Marić, Boško D. and Stamenković, Olivera and Šimurina, Olivera D. and Krstić, Jugoslav and Veljković, Vlada B.",
year = "2023",
abstract = "A low-cost, highly active CaO-based catalyst was prepared from waste filter cake (WFC) from a sugar beet processing factory by calcination in air at 900 °C for 2 h, referred to as the calcined filter cake (CFC). It was used to catalyze the rapeseed oil transesterification with methanol under mild reaction conditions (methanol-to-oil molar ratio of 9:1, catalyst loading of 4–10 %, and reaction temperature of 40–60 °C). Rapeseed oil was characterized regarding the physicochemical properties and fatty acid profile. Low free fatty acid content (about 2.0 mg KOH/g) allowed the direct use of the base CFC catalyst for rapeseed oil transesterification. Rapeseed oil has more unsaturated fatty acids (about 93 %), with oleic acid as the most abundant, than saturated fatty acids (about 7 %). A simplified model combining the changing mechanism of the reaction and the triacylglycerols mass transfer limitation successfully describes the kinetics of transesterification. A good agreement between the model and the experiment was proved by the mean relative percentage deviation for the conversion degree of only ± 7.43 % (based on 42 data). The apparent reaction rate constant follows the Arrhenius equation with the activation energy of 51.9 kJ mol−1. The FAME content higher than 96.5 % can be obtained in wide ranges of the catalyst amount (4–10 %) and the reaction time (about 45–70 min). The following conditions were optimum: the reaction temperature of 59.2 °C, the catalyst loading of 9.1 % (based on the oil weight), and the reaction time of 47 min.",
publisher = "Elsevier",
journal = "Fuel",
title = "Kinetics and optimization of biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing plant",
volume = "334",
pages = "126581",
doi = "10.1016/j.fuel.2022.126581"
}

Nježić, Z., Kostić, M. D., Marić, B. D., Stamenković, O., Šimurina, O. D., Krstić, J.,& Veljković, V. B.. (2023). Kinetics and optimization of biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing plant. in Fuel
Elsevier., 334, 126581.
https://doi.org/10.1016/j.fuel.2022.126581

Nježić Z, Kostić MD, Marić BD, Stamenković O, Šimurina OD, Krstić J, Veljković VB. Kinetics and optimization of biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing plant. in Fuel. 2023;334:126581.
doi:10.1016/j.fuel.2022.126581 .

Nježić, Zvonko, Kostić, Milan D., Marić, Boško D., Stamenković, Olivera, Šimurina, Olivera D., Krstić, Jugoslav, Veljković, Vlada B., "Kinetics and optimization of biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing plant" in Fuel, 334 (2023):126581,
https://doi.org/10.1016/j.fuel.2022.126581 . .

TY  - JOUR
AU  - Veličković, Ana
AU  - Avramović, Jelena M.
AU  - Kostić, Milan
AU  - Krstić, Jugoslav
AU  - Stamenković, Olivera
AU  - Veljković, Vlada B.
PY  - 2021
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/4844
AB  - Wheat straw ash (WSA) was investigated as a new catalyst in biodiesel production from sunflower oil. The catalyst was characterized by temperature-programmed decomposition, X-ray powder diffraction, Hg porosimetry, N2 physisorption, and scanning electron microscopy - energy dispersive X-ray spectroscopy methods. The methanolysis reaction was tested in the temperature range of 55–65 oC, the catalyst loading range 10–20 % of the oil weight, and the methanol-to-oil molar ratio range 18 : 1–24 : 1. The reaction conditions of the sunflower oil methanolysis over WSA were optimized by using the response surface methodology in combination with the historical experimental design. The optimum process conditions ensuring the highest fatty acid methyl esters (FAME) content of 98.6 % were the reaction temperature of 60.3 oC, the catalyst loading of 11.6 % (based on the oil weight), the methanol-to-oil molar ratio of 18.3 :1, and the reaction time of 124 min. The values of the statistical criteria, such as coefficients of determination (R2 = 0.811, R2pred = 0.789, R2adj = 0.761) and the mean relative percent deviation (MRPD) value of 10.6 % (66 data) implied the acceptability and precision of the developed model. The FAME content after 4 h of reaction under the optimal conditions decreased to 37, 12, and 3 %, after the first, second, and third reuse, respectively.
AB  - Pepeo pšenične slame (PPS) je korišćen kao katalizator u proizvodnji biodizela iz sunco-kretovog ulja. Karakterizacija katalizatora je izvršena primenom metoda tempera-turski programiranom razgradnjom (temperature-programmed decomposition, TPDe), rentgenskom difrakcijom (X-ray diffraction, XRD), Hg porozimetrijom, N2 fizi-sorpcijom i skenirajućom elektronskom mikrosopijom sa energo-disperzivnom spek-trometrijom (scanning electron microscopy and energy dispersive X-ray spectroscopy, SEM-EDS). Reakcija metanolize istraživana je pri sledećim reakcionim uslovima: tem-peraturni opseg 55-65 °C; količina katalizatora 10-20 % (računato na masu ulja) i opseg molskog odnosa methanol : ulje 18 : 1 – 24 : 1. Optimizacija reakcionih uslova izvršena je metodologijom površine odziva u kombinaciji sa istorijskim eksperimentalnim planom. Maksimalni prinos metil estara masnih kiselina (MEMK) od 98,6 % postignut je pri sledećim optimalnim reakcionim uslovima: temperatura 60,3 oC, količina katalizatora 11,6 % (računato na masu ulja), molski odnos methanol : ulje 18,3 : 1 i vreme trajanja reakcije 124 min. Vrednosti koeficijenata determinacije (R2 = 0,811, R2pred = 0,789, R2adj = 0,761) i srednjeg relativnog odstupanja (10,6 %, 66 podataka) ukazali su na prihvatljivost i pouzdanost razvijenog modela. Sadržaj MEMK nakon 4 h reakcije pri optimalnim uslovima smanjen je na 37, 12 i 3 % nakon prve, druge i treće upotrebe katalizatora, redom.
PB  - Belgrade : Association of the Chemical Engineers of Serbia
T2  - Hemijska industrija
T1  - Modeling the biodiesel production using the wheat straw ash as a catalyst
T1  - Pepeo pšenične slame kao katalizator u proizvodnji biodizela
VL  - 75
IS  - 5
SP  - 257
EP  - 276
DO  - 10.2298/HEMIND210526028V
ER  - 

@article{
author = "Veličković, Ana and Avramović, Jelena M. and Kostić, Milan and Krstić, Jugoslav and Stamenković, Olivera and Veljković, Vlada B.",
year = "2021",
abstract = "Wheat straw ash (WSA) was investigated as a new catalyst in biodiesel production from sunflower oil. The catalyst was characterized by temperature-programmed decomposition, X-ray powder diffraction, Hg porosimetry, N2 physisorption, and scanning electron microscopy - energy dispersive X-ray spectroscopy methods. The methanolysis reaction was tested in the temperature range of 55–65 oC, the catalyst loading range 10–20 % of the oil weight, and the methanol-to-oil molar ratio range 18 : 1–24 : 1. The reaction conditions of the sunflower oil methanolysis over WSA were optimized by using the response surface methodology in combination with the historical experimental design. The optimum process conditions ensuring the highest fatty acid methyl esters (FAME) content of 98.6 % were the reaction temperature of 60.3 oC, the catalyst loading of 11.6 % (based on the oil weight), the methanol-to-oil molar ratio of 18.3 :1, and the reaction time of 124 min. The values of the statistical criteria, such as coefficients of determination (R2 = 0.811, R2pred = 0.789, R2adj = 0.761) and the mean relative percent deviation (MRPD) value of 10.6 % (66 data) implied the acceptability and precision of the developed model. The FAME content after 4 h of reaction under the optimal conditions decreased to 37, 12, and 3 %, after the first, second, and third reuse, respectively., Pepeo pšenične slame (PPS) je korišćen kao katalizator u proizvodnji biodizela iz sunco-kretovog ulja. Karakterizacija katalizatora je izvršena primenom metoda tempera-turski programiranom razgradnjom (temperature-programmed decomposition, TPDe), rentgenskom difrakcijom (X-ray diffraction, XRD), Hg porozimetrijom, N2 fizi-sorpcijom i skenirajućom elektronskom mikrosopijom sa energo-disperzivnom spek-trometrijom (scanning electron microscopy and energy dispersive X-ray spectroscopy, SEM-EDS). Reakcija metanolize istraživana je pri sledećim reakcionim uslovima: tem-peraturni opseg 55-65 °C; količina katalizatora 10-20 % (računato na masu ulja) i opseg molskog odnosa methanol : ulje 18 : 1 – 24 : 1. Optimizacija reakcionih uslova izvršena je metodologijom površine odziva u kombinaciji sa istorijskim eksperimentalnim planom. Maksimalni prinos metil estara masnih kiselina (MEMK) od 98,6 % postignut je pri sledećim optimalnim reakcionim uslovima: temperatura 60,3 oC, količina katalizatora 11,6 % (računato na masu ulja), molski odnos methanol : ulje 18,3 : 1 i vreme trajanja reakcije 124 min. Vrednosti koeficijenata determinacije (R2 = 0,811, R2pred = 0,789, R2adj = 0,761) i srednjeg relativnog odstupanja (10,6 %, 66 podataka) ukazali su na prihvatljivost i pouzdanost razvijenog modela. Sadržaj MEMK nakon 4 h reakcije pri optimalnim uslovima smanjen je na 37, 12 i 3 % nakon prve, druge i treće upotrebe katalizatora, redom.",
publisher = "Belgrade : Association of the Chemical Engineers of Serbia",
journal = "Hemijska industrija",
title = "Modeling the biodiesel production using the wheat straw ash as a catalyst, Pepeo pšenične slame kao katalizator u proizvodnji biodizela",
volume = "75",
number = "5",
pages = "257-276",
doi = "10.2298/HEMIND210526028V"
}

Veličković, A., Avramović, J. M., Kostić, M., Krstić, J., Stamenković, O.,& Veljković, V. B.. (2021). Modeling the biodiesel production using the wheat straw ash as a catalyst. in Hemijska industrija
Belgrade : Association of the Chemical Engineers of Serbia., 75(5), 257-276.
https://doi.org/10.2298/HEMIND210526028V

Veličković A, Avramović JM, Kostić M, Krstić J, Stamenković O, Veljković VB. Modeling the biodiesel production using the wheat straw ash as a catalyst. in Hemijska industrija. 2021;75(5):257-276.
doi:10.2298/HEMIND210526028V .

Veličković, Ana, Avramović, Jelena M., Kostić, Milan, Krstić, Jugoslav, Stamenković, Olivera, Veljković, Vlada B., "Modeling the biodiesel production using the wheat straw ash as a catalyst" in Hemijska industrija, 75, no. 5 (2021):257-276,
https://doi.org/10.2298/HEMIND210526028V . .