Liam McMillan - The observation of equilibria present in stepwise gas phase hydrogenation reactions

Version 1

      Publication Details (including relevant citation   information):

        Catalysis Today,   155 (3-4). pp. 206-213

        McFarlane, A., McMillan, L., Silverwood, I.  , Hamilton, N.G., Siegel, D., Parker, S.F., Lundie, D.T., and   Lennon,   D.

      Abstract:

        The hydrogenation of a number of C5 olefins (pent-1-ene,   trans-pent-2-ene, cis-pent-2-ene, trans-1,3-pentadiene and a   technical mixture of 1,3-pentadiene) over a 1% Pd/Al2O3 catalyst   has been studied using in situ infrared spectroscopic methods to   observe the changes in the gas phase molecules during the course   of the reaction. Whereas trans-pent-2-ene is directly   hydrogenated to pentane, the reaction profile for cis-pent-2-ene   indicates a consecutive process involving the formation of   gaseous trans-pent-2-ene as a reaction intermediate. Extending   these studies to trans-1,3-pentadiene shows the terminal double   bond to be hydrogenated first to produce trans-pent-2-ene in the   gas phase, which is then subsequently hydrogenated to the alkane.   A reaction scheme is proposed that defines how the molecules are   partitioned between the gaseous and adsorbed phases. This scheme   makes use of a previously postulated two-site adsorption model.   Analysis of a technical grade of 1,3-pentadiene indicates the   trans-monoene to play a significant role in the stepwise   hydrogenation process.

      Address (URL): http://www.sciencedirect.com/science/article/pii/S0920586109006592