TY - JOUR A1 - Brzezinka, Klaus-Werner A1 - Trunschke, A. A1 - Hoang, D. L. A1 - Radnik, J. A1 - Brückner, A. A1 - Lieske, H. T1 - Transition metal oxide/carbon composite catalysts for n-alkane aromatization: Structure and catalytic properties JF - Applied catalysis / A N2 - Nanocrystalline particles of high temperature pretreated titania, zirconia or hafnium oxide, embedded in a carbon matrix, have been found to catalyze the aromatization of n-octane into ethylbenzene (EB) and o-xylene (OX) with high selectivity. The carbon matrix itself is catalytically not active, but seems to co-operate with the transition metal oxides in such a way that the various metal oxide/carbon composite materials exhibit equal selectivity patterns. In detail, the carbon component stabilizes a high dispersion of the oxides during the high temperature pretreatment procedure. This thermal treatment results in a destruction of surface acidity of the oxides, which would otherwise be responsible for undesirable consecutive and parallel reactions. Moreover, the carbon component is involved in the deep dehydrogenation of alkanes to multiple unsaturated alkenes. This is explained by the ability of surface carbon atoms to interact with hydrogen. The bulk and surface structure of the catalysts have been characterized by XRD, specific surface area measurements, XPS, UPS, Raman spectroscopy, in situ ESR and DRIFT spectroscopy. KW - Aromatization KW - Dehydrocyclization KW - n-Octane KW - Monofunctional catalysts KW - Zirconia KW - Titania KW - Oxide/carbon composites PY - 2001 DO - https://doi.org/10.1016/S0926-860X(00)00736-5 SN - 0926-860X SN - 1873-3875 VL - 208 IS - 1-2 SP - 381 EP - 392 PB - Elsevier CY - Amsterdam AN - OPUS4-1083 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -