TY  - JOUR
AU  - Adnađević, Borivoj
AU  - Koturević, Biljana
AU  - Jovanović, Jelena
PY  - 2017
UR  - http://jakov.kpu.edu.rs/handle/123456789/788
AB  - The kinetics of the isothermal extraction of caffeine from the guarana seed powder with water under conventional (CH) and microwave heating (MWH) were investigated. By applying the isoconversional method, it was established that the kinetics of the caffeine extraction under CH and also under MWH is an elementary kinetic process. The model fitting method was used to determine the kinetics model of caffeine extraction. It was found that the kinetics of the caffeine extraction for both heating modes can be described by the Jander's equation. The rate of the extraction of caffeine under MWH is similar to 2 times higher than under CH. The values of kinetics parameters (Ea and lnA) of the extraction process under MWH are lower than for CH. The established influence of MWH on the kinetics of caffeine extraction is explained with a specific activation mechanism of water molecules and with an increase in the energy of the ground vibration level of resonant oscillator of N-3-CH3 band of caffeine molecule (v=317 cm(-1)) which is caused by the absorption of microwave energy.
PB  - Inst Chemical Engineers, Rugby
T2  - Chemical engineering research & design
T1  - Comparative kinetic analysis of isothermal extraction of caffeine from guarana seed under conventional and microwave heating
VL  - 118
SP  - 61
EP  - 70
DO  - 10.1016/j.cherd.2016.12.006
ER  - 

@article{
author = "Adnađević, Borivoj and Koturević, Biljana and Jovanović, Jelena",
year = "2017",
abstract = "The kinetics of the isothermal extraction of caffeine from the guarana seed powder with water under conventional (CH) and microwave heating (MWH) were investigated. By applying the isoconversional method, it was established that the kinetics of the caffeine extraction under CH and also under MWH is an elementary kinetic process. The model fitting method was used to determine the kinetics model of caffeine extraction. It was found that the kinetics of the caffeine extraction for both heating modes can be described by the Jander's equation. The rate of the extraction of caffeine under MWH is similar to 2 times higher than under CH. The values of kinetics parameters (Ea and lnA) of the extraction process under MWH are lower than for CH. The established influence of MWH on the kinetics of caffeine extraction is explained with a specific activation mechanism of water molecules and with an increase in the energy of the ground vibration level of resonant oscillator of N-3-CH3 band of caffeine molecule (v=317 cm(-1)) which is caused by the absorption of microwave energy.",
publisher = "Inst Chemical Engineers, Rugby",
journal = "Chemical engineering research & design",
title = "Comparative kinetic analysis of isothermal extraction of caffeine from guarana seed under conventional and microwave heating",
volume = "118",
pages = "61-70",
doi = "10.1016/j.cherd.2016.12.006"
}

Adnađević, B., Koturević, B.,& Jovanović, J.. (2017). Comparative kinetic analysis of isothermal extraction of caffeine from guarana seed under conventional and microwave heating. in Chemical engineering research & design
Inst Chemical Engineers, Rugby., 118, 61-70.
https://doi.org/10.1016/j.cherd.2016.12.006

Adnađević B, Koturević B, Jovanović J. Comparative kinetic analysis of isothermal extraction of caffeine from guarana seed under conventional and microwave heating. in Chemical engineering research & design. 2017;118:61-70.
doi:10.1016/j.cherd.2016.12.006 .

Adnađević, Borivoj, Koturević, Biljana, Jovanović, Jelena, "Comparative kinetic analysis of isothermal extraction of caffeine from guarana seed under conventional and microwave heating" in Chemical engineering research & design, 118 (2017):61-70,
https://doi.org/10.1016/j.cherd.2016.12.006 . .

TY  - JOUR
AU  - Koturević, Biljana
AU  - Adnađević, Borivoj
AU  - Jovanović, Jelena
PY  - 2017
UR  - http://jakov.kpu.edu.rs/handle/123456789/774
AB  - The kinetics of isothermal green microwaveassisted extraction of caffeine from guarana seed powder with water at a temperature range from 40 degrees C to 60 degrees C was investigated. The caffeine concentration in the water extract was determined by UV-Vis spectrophotometry. By applying the isoconversional method, it was established that the kinetics of the caffeine extraction from the guarana seed powder with microwave heating is an elementary kinetic process. The model fitting method was used to determine the kinetic model of the caffeine extraction under microwave heating. It was found that the kinetics of the caffeine extraction can, under microwave heating, be modeled by the Jander's model of three dimensional diffusion. The kinetic parameters, activation energy and pre-exponential factor of the caffeine extraction were determined.
PB  - Walter De Gruyter Gmbh, Berlin
T2  - Green processing and synthesis
T1  - Isothermal green microwave-assisted extraction of caffeine from guarana: a kinetic study
VL  - 6
IS  - 6
SP  - 555
EP  - 563
DO  - 10.1515/gps-2016-0135
ER  - 

@article{
author = "Koturević, Biljana and Adnađević, Borivoj and Jovanović, Jelena",
year = "2017",
abstract = "The kinetics of isothermal green microwaveassisted extraction of caffeine from guarana seed powder with water at a temperature range from 40 degrees C to 60 degrees C was investigated. The caffeine concentration in the water extract was determined by UV-Vis spectrophotometry. By applying the isoconversional method, it was established that the kinetics of the caffeine extraction from the guarana seed powder with microwave heating is an elementary kinetic process. The model fitting method was used to determine the kinetic model of the caffeine extraction under microwave heating. It was found that the kinetics of the caffeine extraction can, under microwave heating, be modeled by the Jander's model of three dimensional diffusion. The kinetic parameters, activation energy and pre-exponential factor of the caffeine extraction were determined.",
publisher = "Walter De Gruyter Gmbh, Berlin",
journal = "Green processing and synthesis",
title = "Isothermal green microwave-assisted extraction of caffeine from guarana: a kinetic study",
volume = "6",
number = "6",
pages = "555-563",
doi = "10.1515/gps-2016-0135"
}

Koturević, B., Adnađević, B.,& Jovanović, J.. (2017). Isothermal green microwave-assisted extraction of caffeine from guarana: a kinetic study. in Green processing and synthesis
Walter De Gruyter Gmbh, Berlin., 6(6), 555-563.
https://doi.org/10.1515/gps-2016-0135

Koturević B, Adnađević B, Jovanović J. Isothermal green microwave-assisted extraction of caffeine from guarana: a kinetic study. in Green processing and synthesis. 2017;6(6):555-563.
doi:10.1515/gps-2016-0135 .

Koturević, Biljana, Adnađević, Borivoj, Jovanović, Jelena, "Isothermal green microwave-assisted extraction of caffeine from guarana: a kinetic study" in Green processing and synthesis, 6, no. 6 (2017):555-563,
https://doi.org/10.1515/gps-2016-0135 . .