CER - Central Repository
Institute of Chemistry, Technology and Metallurgy
    • English
    • Српски
    • Српски (Serbia)
  • English 
    • English
    • Serbian (Cyrilic)
    • Serbian (Latin)
  • Login
View Item 
  •   Central Repository
  • IHTM
  • Radovi istraživača / Researchers' publications
  • View Item
  •   Central Repository
  • IHTM
  • Radovi istraživača / Researchers' publications
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Non-isothermal reduction of silica-supported nickel catalyst precursors in hydrogen atmosphere: a kinetic study and statistical interpretation

Authorized Users Only
2014
Authors
Jankovic, Bojan
Čupić, Željko
Jovanović, Dušan M.
Article (Published version)
Metadata
Show full item record
Abstract
A series of silica-supported nickel catalyst precursors was synthesized with different SiO2/Ni mole ratios (0.20, 0.80 and 1.15). Non-isothermal reduction of Ni catalyst precursors was investigated by temperature-programmed reduction at four different heating rates (2, 5, 10 and 20 A degrees C min(-1)), in a hydrogen atmosphere. Kinetic parameters (E (a), A) were determined using Friedman isoconversional method. It was found that for all mole ratios, apparent activation energy is practically constant in conversion range of alpha = 30-70 %. In considered conversion range, the following values of apparent activation energy were found: E (a) = 129.5 kJ mol(-1) (SiO2/Ni = 0.20), E (a) = 133.8 kJ mol(-1) (SiO2/Ni = 0.80) and E (a) = 125.0 kJ mol(-1) (SiO2/Ni = 1.15). Using two special functions (y(alpha) and z(alpha)), the kinetic model was determined. It was established that reduction of Ni catalyst precursors with different SiO2/Ni mole ratios is a complex process and can be described by ...two-parameter estak-Berggren (SB) autocatalytic model. Based on established values of SB parameters for each mole ratio, the possible mechanism was discussed. It was found that for all investigated ratios, the Weibull distribution function fits very well the experimental data, in the wide range of conversions (alpha = 5-95 %). Based on obtained values of Weibull shape parameter (theta), it was found that experimentally evaluated density distribution functions of the apparent activation energies can be approximated by the unbalanced peaked normal distribution.

Keywords:
Temperature-programmed reduction (TPR) / SiO2/Ni catalysts / Kinetics / Sestak-Berggren autocatalytic model / IPPC function
Source:
Journal of the Iranian Chemical Society, 2014, 11, 6, 1743-1758
Publisher:
  • Springer, New York
Projects:
  • Dynamics of nonlinear physicochemical and biochemical systems with modeling and predicting of their behavior under nonequilibrium conditions (RS-172015)
  • Nanostructured Functional and Composite Materials in Catalytic and Sorption Processes (RS-45001)

DOI: 10.1007/s13738-014-0447-1

ISSN: 1735-207X

WoS: 000344082600027

Scopus: 2-s2.0-84910598392
[ Google Scholar ]
3
3
URI
http://cer.ihtm.bg.ac.rs/handle/123456789/1405
Collections
  • Radovi istraživača / Researchers' publications
Institution
IHTM
TY  - JOUR
AU  - Jankovic, Bojan
AU  - Čupić, Željko
AU  - Jovanović, Dušan M.
PY  - 2014
UR  - http://cer.ihtm.bg.ac.rs/handle/123456789/1405
AB  - A series of silica-supported nickel catalyst precursors was synthesized with different SiO2/Ni mole ratios (0.20, 0.80 and 1.15). Non-isothermal reduction of Ni catalyst precursors was investigated by temperature-programmed reduction at four different heating rates (2, 5, 10 and 20 A degrees C min(-1)), in a hydrogen atmosphere. Kinetic parameters (E (a), A) were determined using Friedman isoconversional method. It was found that for all mole ratios, apparent activation energy is practically constant in conversion range of alpha = 30-70 %. In considered conversion range, the following values of apparent activation energy were found: E (a) = 129.5 kJ mol(-1) (SiO2/Ni = 0.20), E (a) = 133.8 kJ mol(-1) (SiO2/Ni = 0.80) and E (a) = 125.0 kJ mol(-1) (SiO2/Ni = 1.15). Using two special functions (y(alpha) and z(alpha)), the kinetic model was determined. It was established that reduction of Ni catalyst precursors with different SiO2/Ni mole ratios is a complex process and can be described by two-parameter estak-Berggren (SB) autocatalytic model. Based on established values of SB parameters for each mole ratio, the possible mechanism was discussed. It was found that for all investigated ratios, the Weibull distribution function fits very well the experimental data, in the wide range of conversions (alpha = 5-95 %). Based on obtained values of Weibull shape parameter (theta), it was found that experimentally evaluated density distribution functions of the apparent activation energies can be approximated by the unbalanced peaked normal distribution.
PB  - Springer, New York
T2  - Journal of the Iranian Chemical Society
T1  - Non-isothermal reduction of silica-supported nickel catalyst precursors in hydrogen atmosphere: a kinetic study and statistical interpretation
VL  - 11
IS  - 6
SP  - 1743
EP  - 1758
DO  - 10.1007/s13738-014-0447-1
ER  - 
@article{
author = "Jankovic, Bojan and Čupić, Željko and Jovanović, Dušan M.",
year = "2014",
url = "http://cer.ihtm.bg.ac.rs/handle/123456789/1405",
abstract = "A series of silica-supported nickel catalyst precursors was synthesized with different SiO2/Ni mole ratios (0.20, 0.80 and 1.15). Non-isothermal reduction of Ni catalyst precursors was investigated by temperature-programmed reduction at four different heating rates (2, 5, 10 and 20 A degrees C min(-1)), in a hydrogen atmosphere. Kinetic parameters (E (a), A) were determined using Friedman isoconversional method. It was found that for all mole ratios, apparent activation energy is practically constant in conversion range of alpha = 30-70 %. In considered conversion range, the following values of apparent activation energy were found: E (a) = 129.5 kJ mol(-1) (SiO2/Ni = 0.20), E (a) = 133.8 kJ mol(-1) (SiO2/Ni = 0.80) and E (a) = 125.0 kJ mol(-1) (SiO2/Ni = 1.15). Using two special functions (y(alpha) and z(alpha)), the kinetic model was determined. It was established that reduction of Ni catalyst precursors with different SiO2/Ni mole ratios is a complex process and can be described by two-parameter estak-Berggren (SB) autocatalytic model. Based on established values of SB parameters for each mole ratio, the possible mechanism was discussed. It was found that for all investigated ratios, the Weibull distribution function fits very well the experimental data, in the wide range of conversions (alpha = 5-95 %). Based on obtained values of Weibull shape parameter (theta), it was found that experimentally evaluated density distribution functions of the apparent activation energies can be approximated by the unbalanced peaked normal distribution.",
publisher = "Springer, New York",
journal = "Journal of the Iranian Chemical Society",
title = "Non-isothermal reduction of silica-supported nickel catalyst precursors in hydrogen atmosphere: a kinetic study and statistical interpretation",
volume = "11",
number = "6",
pages = "1743-1758",
doi = "10.1007/s13738-014-0447-1"
}
Jankovic B, Čupić Ž, Jovanović DM. Non-isothermal reduction of silica-supported nickel catalyst precursors in hydrogen atmosphere: a kinetic study and statistical interpretation. Journal of the Iranian Chemical Society. 2014;11(6):1743-1758
Jankovic, B., Čupić, Ž.,& Jovanović, D. M. (2014). Non-isothermal reduction of silica-supported nickel catalyst precursors in hydrogen atmosphere: a kinetic study and statistical interpretation.
Journal of the Iranian Chemical SocietySpringer, New York., 11(6), 1743-1758.
https://doi.org/10.1007/s13738-014-0447-1
Jankovic Bojan, Čupić Željko, Jovanović Dušan M., "Non-isothermal reduction of silica-supported nickel catalyst precursors in hydrogen atmosphere: a kinetic study and statistical interpretation" 11, no. 6 (2014):1743-1758,
https://doi.org/10.1007/s13738-014-0447-1 .

DSpace software copyright © 2002-2015  DuraSpace
About CeR – Central Repository | Send Feedback

OpenAIRERCUB
 

 

All of DSpaceInstitutionsAuthorsTitlesSubjectsThis institutionAuthorsTitlesSubjects

Statistics

View Usage Statistics

DSpace software copyright © 2002-2015  DuraSpace
About CeR – Central Repository | Send Feedback

OpenAIRERCUB