TY - JOUR
T1 - Syngas production from CH 4 dry reforming over Co-Ni/Al 2O 3 catalyst
T2 - Coupled reaction-deactivation kinetic analysis and the effect of O 2 co-feeding on H 2:CO ratio
AU - Foo, Say Yei
AU - Cheng, Chin Kui
AU - Nguyen, Tuan Huy
AU - Adesina, Adesoji A.
N1 - Funding Information:
The authors acknowledge support from the Australian Research Council. SYF and CKC are recipients of the Australian Postgraduate Award and University International Postgraduate Award scholarships respectively.
PY - 2012/11
Y1 - 2012/11
N2 - The dry and oxidative dry reforming of CH 4 over alumina-supported Co-Ni catalysts were investigated over 72-h longevity experiments. The deactivation behaviour at low CO 2:CH 4 ratio (≤2) suggests that carbon deposition proceeds via a rapid dehydropolymerisation step resulting in the blockage of active sites and loss in CO 2 consumption. In particular, at high temperatures of 923 K and 973 K, a 'breakthrough' point was observed in which deactivation that was previously slow suddenly accelerated, indicating rapid polymerisation of deposited carbon. Only with feed CO 2:CH 4 > 2 or with O 2 co-feeding was coke-induced deactivation eliminated. In particular, O 2 co-feeding gave improved carbon removal, product H 2:CO ratios more suitable for downstream GTL processing and stable catalytic performance. Conversion-time data were adequately fitted to the generalised Levenspiel reaction-deactivation model. Activation energy estimate (66-129 kJ mol -1) was dependent on the CO 2:CH 4 ratio but representative of other hydrocarbon reforming reactions on Ni-based catalysts.
AB - The dry and oxidative dry reforming of CH 4 over alumina-supported Co-Ni catalysts were investigated over 72-h longevity experiments. The deactivation behaviour at low CO 2:CH 4 ratio (≤2) suggests that carbon deposition proceeds via a rapid dehydropolymerisation step resulting in the blockage of active sites and loss in CO 2 consumption. In particular, at high temperatures of 923 K and 973 K, a 'breakthrough' point was observed in which deactivation that was previously slow suddenly accelerated, indicating rapid polymerisation of deposited carbon. Only with feed CO 2:CH 4 > 2 or with O 2 co-feeding was coke-induced deactivation eliminated. In particular, O 2 co-feeding gave improved carbon removal, product H 2:CO ratios more suitable for downstream GTL processing and stable catalytic performance. Conversion-time data were adequately fitted to the generalised Levenspiel reaction-deactivation model. Activation energy estimate (66-129 kJ mol -1) was dependent on the CO 2:CH 4 ratio but representative of other hydrocarbon reforming reactions on Ni-based catalysts.
KW - Cobalt-nickel catalyst
KW - Deactivation kinetics
KW - H :CO ratio
KW - Oxidative CO reforming of CH
KW - Time-on-stream behaviour
UR - http://www.scopus.com/inward/record.url?scp=84867846225&partnerID=8YFLogxK
U2 - 10.1016/j.ijhydene.2012.08.136
DO - 10.1016/j.ijhydene.2012.08.136
M3 - Article
AN - SCOPUS:84867846225
SN - 0360-3199
VL - 37
SP - 17019
EP - 17026
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
IS - 22
ER -
