Residence time distribution in three-phase monolith reactor

Ceramic honeycomb monoliths have been used as catalyst supports for gas treatment applications, including automobile catalytic converters and NO{sub x} control in flue-gas treatment. The residence time distribution of the liquid phase within a three-phase monolith reactor is determined using tracer studies. The actual liquid residence time in the monolith, relevant for reactor design purposes, is calculated from overall residence time measurements using deconvolution by Fourier transform. The liquid-phase residence time decreases as liquid or gas flow rates increase, but the reactor Peclet number remains approximately constant. The residence time distribution and calculated values of the Peclet number reveal that the liquid phase is substantially well-mixed. Comparison with results from experiments in a single glass capillary reveals that the monolith channels become predominantly liquid-filled, particularly as the liquid flow rate becomes a significant fraction of the total flow rate.