Effect of surfactant type on interfacial area and liquid mass transfer for CO2 absorption in a bubble column

The effect of different surfactants (n-octyltrimethylammonium bromide (OTABr), sodium dodecyl benzene sulfonate (SDBS) and Tween 80) with different critical micelle concentrations (CMC) on the CO2 absorption into aqueous solutions in a bubble column is analyzed in the present work. The presence of these surfactants increased the gas–liquid interfacial area, and decreased the liquid phase mass transfer coefficient, but with significant different extent. The results indicated that the CMC can be a key parameter affecting the mass transfer of CO2 absorption into a dilute aqueous solution of a surfactant. Sardeing's model was used to fit the experimental data successfully by re-correlating the parameters.

The gas liquid contact device used in our experiments was a cylindrical bubble column made of organic glass. Outside the cylindrical bubble column, a square column was installed with orifices at the lower and upper ends for the inward and outward flow of the circulating water, respectively, to maintain the temperature of the liquid in the bubble column at 25 °C. Another function of the square column was to eliminate the refraction effect caused by the cylindrical surface of the inner column in order to ensure that the bubbles were imaged by the photographic system with no deformation.Figure optionsDownload as PowerPoint slide