The reactions of n-hexane have been studied on 6.3% Pt/SiO, (EUROPT-1) at different hydrogen and n-hexane pressures, and at 543-633 K, over fresh catalyst and over catalysts deactivated by long runs. Turnover numbers are compared with literature data: the differences are attributed to hydrogen pressure effects. Deactivation influences first of all, selectivity. In addition, the 'depth' and ' pattern' of hydrogenolysis have been determined.At low temperature multiple splitting s e e m s to be favoured. lsomerization gives predominantly 3-methylpentane.At medium temperatures, isomerization, C,cyclization and internal splitting prevail ; their ratio is controlled by the hydrogen pressure. The ratio of 2-methylpentane to 3-methylpentane is related to the ratio of internal to terminal rupture. Terminal splitting prevails at highest temperature. Aromatization increases with temperature but s e e m s to be independent of the other reactions. The results are interpreted in terms of three different surface states. These correspond to Pt-H, Pt-C-H and Pt-C under increasing severity of conditions.

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