Modeling Catalytic Trickle-Bed and Upflow Packed-Bed Reactors for Wet Air Oxidation of Phenol with Phase Change

Abstract

In this study, to simulate the steady-state behavior of packed-bed reactors for catalytic wet oxidation of phenol, one-dimensional (1D) axial dispersion model for the liquid phase is coupled with a cell stack model for the gas phase, providing considerable phase change under the selected operating conditions. The reactor scale governing equations, reaction kinetics involved, and solution strategy are discussed. The computational approach accounts for the observed catalyst activities, combined with local transport and catalyst wetting effects. The approach selected is shown to be suitable and efficient in dealing with the problem in question. Comparisons of simulated model predictions and lab scale experimental data are presented. Reasonably simulating the concentration profiles in the reactor at steady-state operation, the model allows designers to determine the effects of catalyst activity and operating and feed conditions on reactor performance. The model also clearly demonstrates the importance of including the phase change effect in the reactor scale flow distribution.

Catalytic wet-air oxidation processes: A review

“…Experimental data, description of mass-transfer processes and reaction courses, as well as reactor simulation activities, which are required for successful commercial exploitation, have so far been presented only for model pollutants such as formic acid, acetic acid, succinic acid, cyclohexanol, cyanide and phenol [20,46,51,81,93,[128][129][130][131][132][133]. Béziat et al [128], who conducted the catalytic oxidation of aqueous solutions of acetic and succinic acid in a trickle-bed reactor, demonstrated that titaniasupported ruthenium catalysts exhibited excellent chemical resistance in a wide range of operating conditions.…”

A Kinetic and Mass Transfer Model for Glycerol Hydrogenolysis in a Trickle-Bed Reactor

“…Trickle-bed models that include the above phenomena have successfully predicted reactor performance in a number of pilot-scale and commercial systems. These include, among others, carbohydrate hydrogenolysis, benzene hydrogenation, catalytic oil hydrotreating, dicyclopentadiene hydrogenation, phenol oxidation, , 1,5,9-cyclododecatriene, phenylacetylene, and 2,4-dinitrotoluene . In all of these studies, partial wetting of the catalyst, gas−liquid and liquid−solid mass transport, and reaction kinetics were incorporated to provide successful descriptions of the reactor behavior.…”

Catalytic Wet Air Oxidation: Are Monolithic Catalysts and Reactors Feasible?

“…Guo and Al-Dahhan , performed comparative studies on column reactors operated in down- and upflow mode. Phenol was oxidized in the presence of granular Al−Fe pillared clay catalyst.…”