Catalytic Oxidation of Model Waste Aromatic Hydrocarbons in a Dense Fluid

Aromatic compounds dissolved in dense COa (with stoichiometric air) were oxidized at 80-140 bar and 453-573 K. A range of behavior from partial oxidation to complete combustion was observed upon varying the active metal oxide on an Al2O3, support. This process can be joined to supercritical fluid extraction as a waste treatment technology; some of the rates of destruction observed here compare favorably to those obtained for similar compounds in supercritical water or wet-air oxidation processes. The results of experiments where pressure was varied, but reactant mole fractions held constant, suggest the absence of rate-limiting fluid-phase reactions, or of diffusional control; the catalyst itself appears to be the locus of the rate-limiting reactions at these conditions.