Method of separating and recovering carbon dioxide from gaseous mixtures

Claim 1

IN A METHOD OF REMOVING AND RECOVERING CARBON DIOXIDE FROM GASEOUS MIXTURES CONTAINING IT, EMPLOYING AN ABSORBING AQUEOUS SOLUTION OF AN ABSORBENT CONSISTING ESSENTIALLY OF A MEMBER OF THE GROUP CONSISTING OF THE CARBONATES, BORATES, PHOSPHATES, AND PHENOLATES OF AN ALKALINE COMPONENT OF THE GROUP CONSISTING OF THE ALKALI METALS AND AMMONIA, WHICH IS CYCLED BETWEEN AN ABSORPTION STEP IN WHICH THE SOLUTION IS CONTACTED WITH THE GASEOUS MIXTURE TO BE PURIFIED TO ABSORB CARBON DIOXIDE, AND A REGENERATION STEP IN WHICH SAID SOLUTION HAVING ABSORBED CARBON DIOXIDE IS REGENERATED BY REMOVAL OF THE LATTER, THE IMPROVEMENT WHICH COMPRISES PROVIDING ARSENIOUS ANHYDRIDE IN SAID AQUEOUS SOLUTION AND MAINTAINING SAID ARSENIOUS ANHYDRIDE AS THE ACTIVATOR AGENT FOR THE ABSORPTION STEP AND FOR THE REGENERATION STEP CONTINUOUSLY THROUGHOUT SAID ABSORPTION STEP AND SAID REGENERATION STEP, SAID ARSENIOUS ANHYDRIDE BEING MAINTAINED AS SUCH UNDER THE CONDITIONS PREVAILING IN SAID ABSORPTION STEP AND SAID REGENERATION STEP BY DECOMPOSING ARSENATE, SULPHURETTED ARSENICAL COMPOUNDS AND LIKE ARSENIC COMPOUNDS INOPERATIVE IN CO2 ABSORPTION