Adsorption and Fluid-mixing Characteristics of Packed Bed Catalysts with Blow-by Sections Part I. An Empirical Approach to the Problem of Concentration Distribution

Abstract

Adsorption and fluid-mixing characteristics of packed bed catalysts with blow-by sections, those which are effective for rapid catalytic reactions, were measured by means of a pulse technique, and the results obtained by gas chromatography were examined by dynamic analysis. The exit age distribution function, E(θ), for blow-by packed tubes was divided into two parts : the blow-by section, part B, and the residence section, part R, according to the normalized residence time, θ, in the range of θ<1 and θ>1, respectively. For the semicircular blow-by packing, B was found to become maximum at a packing ratio of 13/16. For the cylindrical blow-by packing, the tracer concentration extended into the packing layer, maintaining a more uniform distribution than with either the 13/16 semicircular blow-by packing or full packing. This suggests that the incorporation of cylindrical blow-by sections in packed tube catalysts can improve both the efficiency and the lifespan of this type of catalyst.