An ONIOM Study of Catalytically Active Itronsted Acid Sites of ZSM-5

摘要

Catalytic cracking process is specifically initiated on Br0nsted acid site and the loss of strong Br0nsted acid site is directly correlated with the loss of catalytic activity. In this context we first identified and established the activity of Br0nsted acid sites in three-dimensional ZSM-5 by identifying the preferential occurrence of LUMO orbital at these sites. Critical lowering of HOMO-LUMO energy gap in carbon monoxide adsorbed ZSM-5 compared to free CO2 revealed the cause for high activation of CO.