Selective hydrogenation in trickle-bed reactor. Experimental and modelling including partial wetting.

Adrian Dietz (1) , Carine Julcour-Lebigue (1) , Anne-Marie Wilhelm (1) , Henri Delmas (1)

1 LGC - Laboratoire de Génie Chimique

A steady state model of a trickle bed reactor is developed for the consecutive hydrogenation of 1,5,9-cyclododecatriene on a Pd/Al2O3 catalyst. Various experiments have shown that the selectivity of this reaction towards the product of interest is much lower in co-current down-flow (trickle-bed) than in up-flow. This is due to uneven liquid distribution and to partial wetting of the catalyst surface at low liquid flow rates. The non-isothermal heterogeneous model proposed here takes into account the partial wetting of the catalyst, as well as the resistances to heat and mass transfer at the gas-liquid, liquid-solid and solid-gas interfaces. It assumes that the catalyst particles can be divided into two distinct concentration zones corresponding to the wetted and dry catalyst surfaces; mass transfer between these two zones is described by a simplified diffusion mechanism. Compared to previous models assuming a uniform concentration of liquid-phase components inside the catalyst particles, this model improves the prediction of the outlet concentrations of hydrogenation products.

Mots clés: Trickle-bed reactor; Selective hydrogenation; Trickle-bed modelling

Domaines: Catalyse

Adrian Dietz, Carine Julcour-Lebigue, Anne-Marie Wilhelm, Henri Delmas. Selective hydrogenation in trickle-bed reactor. Experimental and modelling including partial wetting.. Catalysis Today, 2003, vol. 79-80, pp. 293-305. ⟨10.1016/S0920-5861(03)00053-1⟩. ⟨hal-00736480⟩