Homogeneous adsorption of benzene

Acetaldehyde decomposition, reaction pathway control, 14-15 Acetylene, continuous catalytic conversion over metal-modified shape-selective zeolite catalyst, 355-370 Acid-catalyzed shape selectivity in zeolites primary shape selectivity, 209-211 secondary shape selectivity, 211-213 Acid molecular sieves, reactions of m-diisopropylbenzene, 222-230 Activation of C-H, C-C, and C-0 bonds of oxygenates on Rh(l 11) bond-activation sequences, 350-353 divergence of alcohol and aldehyde decarbonylation pathways, 347-351 experimental procedure, 347 Additives, selectivity, 7,8r Adsorption of benzene on NaX and NaY zeolites, homogeneous, See Homogeneous adsorption of benzene on NaX and NaY zeolites... 

Additional measurements of benzene adsorption on a Raney Ni surface which had been precovered with H showed that the adsorption now took placed without C-H rupture and it was suggested that this was because H adsorption had taken place at the dissociation centres. A determination was made of the ring to surface distance, but this was not sufficiently accurate for an assessment to be made of whether or not the benzene formed an adlayer on top of a homogeneous hydrogen layer.86... 

Following the pioneering works of Ito and Fraissard (57) and Ripme-ester (58), 129Xe NMR of xenon adsorbed on zeolite has proven sensitive probe of its local environment due to its chemical inertness and excellent sensitivity (59). In this work, we used 11 and 13C NMR measurements of the adsorbed benzene in conjunction with 129Xe NMR and adsorption isotherm measurements of the co-adsorbed xenon to study the homogeneous adsorption behavior of benzene on faujasite-type zeolites with various Si/Al ratios. Detailed macroscopic and microscopic adsorption states of the benzene in various NaX and NaY zeolites are discussed in terms of NMR linewidths and chemical shifts and are compared with results obtained from other studies. 

Structure. At very low 6, i 1 may be higher because of attachment of adsorptive molecules to grain boundaries between the single crystals of graphite, whereas after completion of the monolayer, the enthalpy drops to (almost) the enthalpy of liquefaction (dashed line in the figure). In fig. 1.8b there Is no such plateau, although from the measurements with benzene It was deduced that the surface is homogeneous. The rise in I I was attributed to lateral interaction... 

According to a multilayer adsorption theory developed by Champion and Halsey such adsorption on a homogeneous surface leads inevitably to step like isotherms and isotherm continuity should be explained by surface heterogeneity [48]. Differences in the relationship course q°( = f(%PEG) between non-polar hexane, polar chloroform, 5r-complexing benzene, acetone and methanol which are capable of hydrogen bonds formation become comprehensible in view of the fact that specific and non-specific interactions, having different adsorption energies, take part in the adsorption process. Formation of distinct extreme on hexane heat of adsorption curve can be explained by hexane non polarity... 

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