Kinetic investigations of the deactivation by coking of a noble metal catalyst in the catalytic hydrogenation of nitrobenzene using a catalytic wall reactor

摘要: Abstract The vapour phase hydrogenation of nitrobenzene to aniline is a highly exothermic reaction deactivated by coking the palladium catalyst supported on α-alumina carrier. For studying deactivation catalytic wall reactor was used in order ensure isothermal conditions for kinetic measurements. Furthermore, allowed determination axial coke profiles total carbon analysis different segments. On assumption that main and can be assumed separable both steady state unsteady kinetics were studied. Nitrobenzene identified as relevant precursor whereas has neither an influence nor deactivation. It could shown follows Langmuir–Hinshelwood mechanism considering surface adsorbed molecule one hydrogen atom rate determining step. differentiation active sites support must taken into account model formation with sufficient accuracy.