Mass transfer phenomena were studied in a slurry bubble column in which fine acicular α-Goe-thite partiicles(average length 0.27㎛) were suspended in 1N-NaOH solution. In order to measure bubble diameter, two-point probe was used. Distribution of measured bubble diameters in the slurry bubble column was showed log-normal and changed from unimodal to multimodal with increasing the superfiicial gas velocity and solid concentration. Sauter mean bubble diameter(d_vs, volume-to-surface mean bubble diameter)was minimized at transition region, but above that region, it was increased by increasing superficial gas velocity and solid concentrations. Liquid side mass transfer coefficient(k_L) was increased below 0.9wt% solid concen-tration but was suddenly decreased above 0.9wt% by concentrationg the solid. The k_L was also increased with increasing the Sauter mean bubble diameter. Liquid side mass transfer confficient can be represented as following equation by dimensionless groups and wt% concentration on this system and conditions.
Sh=1.0×10^-5Sc^1.53Re^0.79Bo^0.51/(1+8.×Φ^2.73)