Absorption Kinetics of CO₂ in Aqueous Ammonia with High Load and Salinity

Abstract

In order to improve the absorption efficiency of carbon dioxide (CO 2 ) in the process of inorganic ammonia carbon capture, it is critical to find out the factors inhibiting CO 2 absorption. In this work, the mass transfer flux of CO 2 is measured by a multi-column wetted wall reactor. The results indicated that the boundary concentration of NH 3 under the conditions of chemical reaction is 1.01527 kmol•m −3 . The contribution of CO 2 concentration in the liquid film to the reaction rate is found to be less than that of NH 3 . The carbonization degree is only related to pH and has nothing to do with the initial concentration of NH 3 . The decrease of absorption efficiency is related to the H + activity coefficient rather than the change of the diffusion coefficient. A flux prediction model with high load and salinity is presented subsequently. Furthermore, the two important regulation indexes are the pH and NH 4 HCO 3 saturation.