The mass-transfer coefficients at varied axial, radial, and angular positions in a packed bed of Pall rings were measured using the limiting current technique. The experimentation was carried out in a 0.30-m-diameter column with a bed height of 5.5 column diameters. Ferri-/ferrocyanide ions were used as the redox couple for the mass-transfer measurement. The local mass-transfer rate was found to be strongly dependent on the liquid feed distribution, especially at the top section of the packed bed. The local mass-transfer rate also varied significantly in the axial and radial directions in the packed bed. A maximum mass-transfer rate was observed at an axial distance of 1.5 column diameters (x/D ) 1.5) when the multipoint liquid distributor was used while the highest transfer rate occurred at x/D ) 2.5 for the single-point liquid distributor. However, for both types of liquid distributors the mass-transfer rate became steady at x/D > 4.5. The wall flow also reached steady-state x/D ) 3.5. The average mass-transfer rate with the multipoint distributor was about 14% higher than that with the single-point distributor.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.