A CO2 amine scrubbing process uses an absorbent mixture combination of an amine containing a primary amino group CO2 sorbent in combination with a non-nucleophilic relatively stronger base. The weaker base(s) are nucleophilic and have the ability to react directly with the CO2 in the gas stream while the relatively stronger bases act as non-nucleophilic promoters for the reaction between the CO2 and the weaker base. Two moles of CO2 can be taken up by the primary amine groups in a dicarboxylation reaction, affording the potential for a highly efficient scrubbing process.