ABSTRACT
A process has been developed for the removal of carbon dioxide from a gaseous stream and for its subsequent transfer to another gas stream by thermal regeneration. The sorbent is a stable mixture of finely ground potassium carbonate with a high surface area commercial aluminum oxide. Seventy percent of the carbonate can be reacted reversibly with a negligible diffusional resistance in the particles. Potassium carbonate was chosen as the sorbent because the decomposition pressure of the bicarbonate is very low near room temperature. The decomposition pressure of sodium bicarbonate appeared to be too high, while the salts of rubidium or cesium require higher regeneration temperatures and are expensive. At low CO2 concentrations, sorption proceeded for a sufficiently long time so one could obtain rates from outlet concentrations of CO2, rather than from the more time consuming series of regeneration runs.
