Process for capturing CO2 from a CO2-containing gas stream using a thermoresponsive copolymer

A process capturing CO2 from a CO2-containing gas stream, contacting a CO2-containing gas stream with a CO2-absorbing agent in an absorption step in a vessel with maximum temperature T1 resulting in absorption of CO2. The CO2 absorbing agent comprising a polymer dissolved in an aqueous medium, the polymer, a thermoresponsive copolymer, comprising amine monomer distributed through the copolymer, subjecting the CO2-containing absorbing agent to a desorption step in a vessel with maximum temperature T2, releasing CO2, wherein T1 is below LCST of the thermoresponsive polymer at maximum CO2 loading, and T2 is above LCST of the thermoresponsive polymer at minimum CO2 loading. CO2 absorbing agent comprises amine component dissolved in the aqueous medium. Use of the specific polymer dissolved in an aqueous medium at T1, wherein amine monomer, distributed through the copolymer with an amine component, improves net CO2 sorption and high absorption speed, allowing a relatively small absorption reactor.