The Nature, Structure, and Composition of Adsorbed Hydrocarbon Products of Ambient Temperature Oligomerization of Ethylene on Acidic Zeolite H-ZSM-5

Screening of different zeolites and silicoaluminophosphates for the retention of propene under cold start conditions

“…On the other hand, high temperature peaks could be associated to the presence of chemical interactions that may lead to oligomer cracking. Oligomer formation is associated with hydroxyl groups attached to the surface of the zeolite that provide sites for aliphatic carbon adsorption that may ultimately lead to oligomerisation [26]. Then, a similar interpretation could be carried out in the case of ZSM-5 and SAPO-41, where several peaks can be identified.…”

Catalytic Activities of Alcohol Transformations Over 8-Ring Zeolites

“…We note, however, there is no reliable method for identifying the Brønsted acid strength, which is essential for the activation of the reactants and further catalyzed reactions in these 8-ring zeolites. Presently, the acid strength can only be estimated by the theoretical modeling [24]. Nevertheless, the poor catalytic performance of H/MTF zeolits upon ethylene transformation indicates that H/MTF might have weaker acidities than H/MFI.…”

In Situ IR Study of the Nature and Mobility of Sorbed Species on H-FER during But-1-ene Isomerization

“…Most of these species diffuse slowly in the zeolite pores. It must also be kept in mind that the physisorbed alkenes are most likely in equilibrium with the corresponding alkoxy species formed by reaction with the Brønsted acid sites (25), although no direct IR evidence of this equilibrium was obtained in the current study.…”

“…The direct evidence for the formation of the alkoxide was not available, because the spectral region below 1200 cm −1 , where ν C-O can be observed (24), was not accessible. Carbenium ions in thermal equilibrium with the alkoxide and butene species may also be present (25); however, the main IR absorption feature of these compounds (CCC asym. stretch at ca.…”