The geometry of catalyst-containing bale packing is characterized in this paper. The calculated packing parameters (specific surface area and void fraction) are employed in conjunction with a model to predict two-phase pressure drop, maximum capacity, and height equivalent to a theoretical plate (HETP). Experimental data obtained in a 5.3-cm (2.1-in.) column, operated at total reflux, are presented for two systems (cyclohexane/n-heptane and acetone/methyl ethyl ketone) at pressures of 138 and 241 kPa (20 and 35 psia). Model predictions for pressure drop and HETP are validated with experimental data obtained under nonreactive conditions. An appropriate procedure for scaleup of HETP and pressure drop, with associated Limitations, is also discussed.