MODELING OF A TRICKLE-BED REACTOR .2. THE HYDROGENATION OF 3-HYDROXYPROPANAL TO 1,3-PROPANEDIOL

1,3-Propanediol can be synthesized by the hydrogenation of 3-hydroxypr opanal over a nickel catalyst. The aim of the investigation was to obt ain information about the mass transfer and degree of wetting in a tri ckle bed reactor. The model for the concentration and temperature prof iles in a pilot reactor employed was based on kinetic measurements in an autoclave. Two different approximations of the overall catalyst eff ectiveness factor were used: (1) the effectiveness factors of dry, hal f wetted and totally wetted slabs were weighted as proposed by Beaudry , Mills and Dudukovic; (2) a new cylinder shell model was used, leadin g to one-dimensional mass balance equations inside the porous catalyst particle for all possible values of the external wetting efficiency o n the particle scale.