In this work, simultaneous hydrodynamics and mass-transfer Computational fluid dynamics (CFD) Studies ill a rectangular partially aerated bubble column were conducted. The proposed transient Eulerian-Eulerian model was applied to a two-phase flow composed of polydispersed air and water. Four different k(1) correlations were implemented in the CFD code, and the results were compared. At superficial gas velocity values ranging from 2.4 mm/s to 21.3 mm/s, the developed flow regimes were experimentally characterized by means of visual observations, global gas holdup, plume oscillation period, and Sauter mean bubble diameter measurements. Simultaneously, the transfer of oxygen from the disperse phase to the initially deoxygenized water was characterized by the measurement of the evolution of the dissolved oxygen concentration with time. Comparison between the experimental and simulated parameters previously mentioned allows for the validation of the computational model. According to the results presented in this work, experimental and simulated hydrodynamic and mass-transfer results show a remarkable agreement at all studied superficial gas velocity values. In addition, mass-transfer results reveal (1) no influence on the developed hydrodynamics, (2) the adequacy of the selected k(1) correlations obtained by all attentive simplification of mass-transfer equations, and (3) the enhancement of mass-transfer processes when using partially aerated bubble columns.