Compared to the conventional MEA process for the capture and separation of carbon dioxide from flue gas, the ammonia scrubbing technique provides several advantages, such as a higher capture efficiency and capacity, lower decomposition temperatures of ammonium bicarbonate, as well as lower costs and less corrosion to absorber material. However, in addition to the highly volatile nature of ammonia, the lack of a method to separate ammonia from CO 2 after thermal decomposition of ammonium bicarbonate also hinders the ammonia scrubbing technique from being applied in practice. This paper investigates a method to regenerate ammonia so as to allow for the ammonia scrubbing technique to be practical in the capture of CO 2 . The new method requires the use of weakly basic ion-exchange resins containing amine functional groups. At ambient temperatures, these resins were found to be effective in the regeneration of ammonia from ammonium bicarbonate, which is the main product formed after the absorption of CO 2 by ammonia. The resin, which absorbed the carbonic acid, can also be regenerated when it is heated by water at temperatures equal to or greater than 50°C. Also, through several runs of a resin absorption-desorption experiment, the sustainability of the resin for the regeneration of ammonia from ammonium bicarbonate was evidently demonstrated.

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