This paper reports on the experimental investigation carried out to evaluate mass transfer characteristics of a hydro-dynamically-induced multi-stage bubble column. As conventional normal bubble column could not meet the high mass transfer rate, this novel bubble column has been conceived, designed and fabricated as a wet scrubber for the control of air pollution; in addition it has versatile use as a gas-liquid contactor in chemical processing industries. Chemical methods have been used to characterize the mass transfer of the novel multi-stage bubble column. A liquid side mass transfer coefficient and a volumetric mass transfer coefficient have been found to be effective and improved from the previous work for such an improved gas-liquid contactor.