TY - JOUR
T1 - On reaction pathways in the conversion of methanol to hydrocarbons on HZSM-5
AU - Sun, Xianyong
AU - Mueller, Sebastian
AU - Liu, Yue
AU - Shi, Hui
AU - Haller, Gary L.
AU - Sanchez-Sanchez, Maricruz
AU - Van Veen, Andre C.
AU - Lercher, Johannes A.
N1 - Funding Information:
The authors acknowledge the financial support from Clariant Produkte (Deutschland) GmbH and fruitful discussions within the framework of MuniCat. X.S. is thankful to Anmin Zheng for helpful discussions.
PY - 2014/8
Y1 - 2014/8
N2 - The underlying mechanisms of the two distinct catalytic cycles operating during conversion of methanol to olefins (MTO) on HZSM-5 have been elucidated under industrially relevant conditions. The co-existence of olefins and aromatic molecules in the zeolite pores leads to competition between the two cycles. Therefore, their importance depends on the local chemical potential of specific carbon species and the methanol conversion. Due to a faster, "autocatalytic" reaction pathway in the olefin based cycle, olefin homologation/cracking is dominant under MTO conditions, irrespective of whether aromatic molecules or olefins are co-fed with methanol. Another hydrogen transfer pathway, faster than the usual route, has been identified, which is directly linked to methanol. In agreement with that, the co-feeding of olefins resulted in a remarkable longer lifetime of the catalyst under MTO conditions, because the high rate methylation competes with the formation of more deactivating coke - presumably oxygenates- through methanol derivatives.
AB - The underlying mechanisms of the two distinct catalytic cycles operating during conversion of methanol to olefins (MTO) on HZSM-5 have been elucidated under industrially relevant conditions. The co-existence of olefins and aromatic molecules in the zeolite pores leads to competition between the two cycles. Therefore, their importance depends on the local chemical potential of specific carbon species and the methanol conversion. Due to a faster, "autocatalytic" reaction pathway in the olefin based cycle, olefin homologation/cracking is dominant under MTO conditions, irrespective of whether aromatic molecules or olefins are co-fed with methanol. Another hydrogen transfer pathway, faster than the usual route, has been identified, which is directly linked to methanol. In agreement with that, the co-feeding of olefins resulted in a remarkable longer lifetime of the catalyst under MTO conditions, because the high rate methylation competes with the formation of more deactivating coke - presumably oxygenates- through methanol derivatives.
KW - Hydrocarbon pool
KW - Mechanism
KW - Methanol to olefins
KW - ZSM-5
UR - http://www.scopus.com/inward/record.url?scp=84904282995&partnerID=8YFLogxK
U2 - 10.1016/j.jcat.2014.06.017
DO - 10.1016/j.jcat.2014.06.017
M3 - Article
AN - SCOPUS:84904282995
SN - 0021-9517
VL - 317
SP - 185
EP - 197
JO - Journal of Catalysis
JF - Journal of Catalysis
ER -