TY - JOUR
T1 - Linear Free Energy Relationships in Kinetic Analyses
T2 - Applications of Quantum Chemistry
AU - Neurock, Matthew
AU - Klein, Michael T.
PY - 1993/9/1
Y1 - 1993/9/1
N2 - The role of linear free energy relationships and quantum chemistry in kinetic analyses is discussed and applied to a representative sequence of molecular pathways important in hydrocracking chemistry. Experimental data on adsorption, hydrogenation, cracking, isomerization, and coking for various aromatic, heteroatom-containing aromatics, and alkylaromatics were compiled from the literature and correlated with a set of reactivity indices which describe important structural, electronic, and/or energetic features of the reactants, products, or intermediates. All reactivity indices were computed from semiempirical quantum chemical calculations. The equilibria of adsorption were correlated with the proton affinity. Hydrogenation kinetics were related to the atomic site containing the highest 7r-electron density. Cracking kinetics were explained by the correlation with the heat of hydride transfer. Isomerization appeared dependent upon the heat of carbocation formation. Coke formation was related to the proton affinity. These LFERs provided a concise organizational summary of the chemistry of hydrocracking. Their potential in the prediction of the kinetics of unstudied systems is also discussed.
AB - The role of linear free energy relationships and quantum chemistry in kinetic analyses is discussed and applied to a representative sequence of molecular pathways important in hydrocracking chemistry. Experimental data on adsorption, hydrogenation, cracking, isomerization, and coking for various aromatic, heteroatom-containing aromatics, and alkylaromatics were compiled from the literature and correlated with a set of reactivity indices which describe important structural, electronic, and/or energetic features of the reactants, products, or intermediates. All reactivity indices were computed from semiempirical quantum chemical calculations. The equilibria of adsorption were correlated with the proton affinity. Hydrogenation kinetics were related to the atomic site containing the highest 7r-electron density. Cracking kinetics were explained by the correlation with the heat of hydride transfer. Isomerization appeared dependent upon the heat of carbocation formation. Coke formation was related to the proton affinity. These LFERs provided a concise organizational summary of the chemistry of hydrocracking. Their potential in the prediction of the kinetics of unstudied systems is also discussed.
KW - hydrocracking chemistry
KW - kinetics
KW - LFER
KW - quantum chemistry
KW - reactivity indices
KW - structure-reactivity
UR - http://www.scopus.com/inward/record.url?scp=84963333706&partnerID=8YFLogxK
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U2 - 10.1080/10406639308009613
DO - 10.1080/10406639308009613
M3 - Article
AN - SCOPUS:84963333706
SN - 1040-6638
VL - 3
SP - 231
EP - 246
JO - Polycyclic Aromatic Compounds
JF - Polycyclic Aromatic Compounds
IS - 4
ER -