OP-II-3

OP-I-13n-HEXANE SKELETAL ISOMERIZATION OVER BYFUNCTIONALCATALYSTS: EXPERIMENT AND KINETIC MODELINGVolkova G.G., Budneva A.A., Paukshtis E.A., Petrov R.V., Reshetnikov S.I.Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5,Novosibirsk, 630090, Russia, E-mail: ggvolkova@catalysis.ruSkeletal isomerization of light naphtha is composed mainly of conversion of n-hydrocarbons C 5 -C 8 into branched alkanes. It allows to increase octane number ofgasoline because multiply branched alkanes have higher octane number than monomethylalkanes, and are preferentially produced at low temperature subject tochemical equilibrium. By the large demand of desired isomerization productsdevelopment of new more active catalysts has been continued. Recently new acidcatalysts based on sulfated zirconia have been developed and successfullycommercialized [1–2]. It is known that activity of the sulfated zirconia catalystssignificantly depends on preparation procedure, the activity of the catalysts with thesame structure and equal in sulfate content may differ by one order of magnitude.Many researchers try to reveal the critical differences determining the variation incatalytic activity and to recognize the important characteristics of the active catalyst.The aim of this work was to investigate the kinetics of n-hexane skeletalisomerisation over bifunctional catalysts with different acidity: Pt/Cs 2 HPW 12 O 40Pt/WO x /ZrO 2 ; Pt/SO 4 /ZrO 2 .The calculation of the rate constants, characterizing the catalyst activity andselectivity was performed on the base of mathematical model of plug flow reactor. Itwas assumed that the reactions are pseudo-first order in reagents. It was shown thatthe rate of hexane isomerization is mainly determined by the density of Lewis acidsites on the surface of catalysts The kinetic constants and activation energies weredetermined. The results of mathematical modeling are in good agreement withexperimental data.References[1]. T. Kimura, Catal. Today 2003, 81, 57.[2]. S.A. Gembicki, Stud. Surf. Sci. Catal. 2000, 130, 147.[3]. X. Li, K. Nagaoka, L.J. Simon, J.A. Lercher, S. Wrabetz, F.C. Jentoft, C.Breitkopf, S. Matysik,H. Paap, J.Catal. 2005, 230, 214.AcknowledgementsThis work is supported by Federal Target Program (FTP) ”Science, Academic andTeaching Staff of Innovative Russia for 2009-2013”. Contract P253.61