Diffuse reflectance ultraviolet spectroscopic study of benzene adsorption on X and Y zeolites

Abstract

Publication costs assisted by the Monsanto Company In order to study changes in the electron structure of benzene as it interacts with the walls of a zeolite supercage, a diffuse reflectance UV study of the -* transition at various benzene loadings has been carried out. In general, red shifts are observed as the benzene loading on a particular zeolite increases. Red shifts are also observed with an increase in the electrostatic field within the supercage whether the increase is accomplished by changing the cation or the Si/Al ratio of the faujasite lattice. Various simple approaches at quantitatively explaining these results fail, but there is some evidence that a full accounting of dispersion, polarization, and quadrupole interactions would be successful.

Investigation of the zeolite catalyzed alkylation of toluene using carbon-13 nuclear magnetic resonance

“…Errors in the shielding tensors are ±1 ppm for benzene, ±6 ppm for hexamethylbenzene and toluene, and ±10 ppm for adsorbed toluene. 6 Neat. c Values calculated assuming Ce rotation averages cr¡¡ and 22 and that C2 rotation averages 22 and a¡3.…”

Sorption of biphenyl in NaX zeolites

“…The perturbation induced by the intracavity electrostatic Ðeld promotes weak red shifts with respect of the solution spectrum. 19 In contrast, increased BP loading in generates marked UV-visible absorption Na 85 FAU wavelength shifts and band shape changes. In addition, the dependence between the absorption intensity, in KubelkaÈ Munk units, with the bulk loading values diverges dramatically from linearity (Fig.…”

Crystal Structure of a Mesitylene Sorption Complex of Dehydrated Fully Ca2+-Exchanged Zeolite X. Sorbed Mesitylene Appears to be Significantly Nonplanar

“…The sorption of PhMe, m -xylene, mesitylene, PhCMe 3 , and PhCH 2 OH on Na−Y, H,Na−Y, Mg,H,Na−Y, and Co,H,Na−Y zeolites was studied by IR . The sorption of benzene by faujasite zeolites was repeatedly investigated by a variety of spectroscopic techniques, including UV, , IR, − and Raman . High-resolution powder neutron-diffraction studies have already been successful in locating a number of hydrocarbon molecules in zeolites, such as benzene, o -, m -, and p -xylene, pyridine, and aniline in zeolite Y and benzene and pyridine in zeolite L. The structures of Yb,Na−Y zeolites containing sorbed perdeuterated xylenes have been studied at two different xylene coverages at 5 K by powder neutron diffraction.…”