Anatase-supported vanadium oxide catalysts for o-xylene oxidation: From consolidated certainties to unexpected effects |
| |
Authors: | Silvia Luciani Nicola Ballarini Fabrizio Cavani Carlotta Cortelli Federico Cruzzolin Alessandra Frattini Roberto Leanza Barbara Panzacchi |
| |
Affiliation: | aDipartimento di Chimica Industriale e dei Materiali, Università di Bologna, INSTM Research Unit of Bologna, Viale Risorgimento 4, 40136 Bologna, Italy;bPolynt SpA, Via E. Fermi 51, 24020 Scanzorosciate (BG), Italy |
| |
Abstract: | In this paper some aspects of the reaction of o-xylene oxidation, catalysed by anatase-supported vanadium oxide, are re-examined and compared with the scientific and patent literature. Specifically, the effect of vanadia loading on turnover frequency and on the distribution of products has been investigated, using catalysts having sub-monolayer and above-monolayer vanadium oxide deposited on a high-purity anatase support. It was found that even catalysts having less-than-monolayer vanadia loading, containing isolated or oligomeric VO4 species, may give good selectivity to phthalic anhydride, provided the support does not catalyze the formation of heavy compounds. Moreover, the effect of water on the reactivity and chemical–physical characteristics of catalysts was studied by means of in situ Raman spectroscopy. Steam promoted dynamic reversible phenomena occurring at the catalyst surface, by facilitating the dispersion of bulk vanadium oxide and therefore increasing the catalyst activity. |
| |
Keywords: | Supported vanadium oxide Anatase o-Xylene oxidation Phthalic anhydride In situ Raman Steam effect |
本文献已被 ScienceDirect 等数据库收录! |
|