Investigation of dynamic surface tension in gas–liquid absorption using a microflow interfacial tensiometer

Surface tension is an important parameter that dominates gas–liquid dual-phase flow. In this study, the dynamic surface tension caused by changing substance concentrations at the gas–liquid interface was determined using a microflow interfacial tensiometer. The instantaneous surface tensions at the bubble rupturing moment in a CO2 chemical absorption process were determined from the bubble diameter. The mass transfer across the interface and the chemical reaction within the liquid caused up to a 7.2 mN m−1 reduction in the surface tension, as compared with that in a process without absorption, and the decrease in the surface tension can be expressed into a Langmuir–Szyszkowski equation of the CO2 interfacial concentration. This study clarifies the effect of chemical absorption on multiphase fluid dynamics parameters, which is less discussed in chemistry and chemical engineering studies.