Application and Mechanism of Superhydrophilic Surfaces for the Enhancement of CO₂–H₂O Absorption

In this work, superhydrophilic packings are employed to intensify the absorption process of CO₂ with H₂O. The results show that the improvement in absorption efficiency with a superhydrophilic surface in the falling film process was 1.7–2 times that for the untreated pristine plate and more than 10% in the packed tower. The enhancement of absorption is caused by the high attraction of the superhydrophilic surface to water, which evokes a stable but relatively thin water film, enlarging the wetted surface area with low water flow and holding more water on the surface with high water flow. The flooding point of the superhydrophilic packings increases by 20% and the water holdup improves by 1.2–1.4 times. The enhancement effect can be introduced by modifying the existing absorption correlation with the parameter of the wetted area ratio of the superhydrophilic surface to the unmodified surface. The intensification of the CO₂/H₂O adsorption process evoked by superhydrophilicity provides a useful strategy for packing reformation.