Process for the recovery of carbon dioxide from a gas stream

A process for recovering CO2 from a feed gas stream comprising:

• a. treating the feed gas stream with a regenerated absorbent having a viscosity less than 15 centistokes that is selected from one the of the following groups:
• i. at least one polyamine in the absence of an effective amount of tertiary amine functionalities having a pKa sufficient to neutralize carbamic acid, the polyamine having at least one primary amine functionality having a pKa of <10.0 at 25° C. wherein and the feed gas stream has an SO2 concentration less than 5 ppm vol.;
• and,
• ii. a polyamine in the absence of an effective amount of tertiary amine functionalities having a pKa sufficient to neutralize carbamic acid, the polyamine having at least one secondary amine functionality having a pKa for each sorbing nitrogen of <10.0 at 25° C.
• to obtain a spent absorbent and a CO2 lean gas stream;
• b. conveying the CO2 rich amine absorbent to a regeneration zone;
• and,
• c. regenerating the absorbent;
• wherein the regenerated and spent absorbents have a difference in CO2 loading per mole of absorbent of 0.4 to 1.0 mole CO2/mole of amine, when treating a feed gas comprising greater than 4 % vol. of CO2.