Process for capturing carbon-dioxide from a gas stream

A process for capturing carbon-dioxide from a gas stream, said process comprising the following steps:

• a) providing a support, wherein said support is one of an alumina support and a silica alumina support;
• b) impregnating potassium carbonate (K2CO3) on said support to form an adsorbent comprising potassium carbonate (K2CO3) impregnated support;
• c) activating said adsorbent in an adsorber by passing one of water-vapor and a gas stream comprising water-vapor at a temperature ranging from 40° C. to 80° C., at a pressure ranging from 1 bar to 2 bar, and for a time period ranging from 1 minute to 20 minutes to form an activated adsorbent with active adsorption sites having reduced energies compared to non-hydrated sites on the adsorbent;
• d) passing said gas stream through said adsorber containing said activated adsorbent to enable adsorption of the carbon-dioxide from said gas stream on said activated adsorbent at a temperature ranging from 40° C. to 90° C. and at a pressure ranging from 1 bar to 2 bar to form a carbon-dioxide laden adsorbent;
• e) transferring said carbon-dioxide laden adsorbent to a desorber;
• and
• f) passing a carbon-dioxide deficient stream through said desorber for at least partially desorbing the carbon-dioxide from said carbon-dioxide laden adsorbent at a temperature ranging from 110° C. to 200° C. and at a pressure ranging from 1 bar to 2 bar to obtain a partially regenerated adsorbent, wherein said carbon-dioxide deficient stream comprises nitrogen, carbon-dioxide, or water-vapor;
• and
• g) returning said partially regenerated adsorbent to said adsorber for adsorbing the carbon-dioxide from said gas stream;
• Wherein,
• the process of impregnation is carried out in the following steps:
• i. treating said support at a temperature in the range of 550° C. to 1100° C. to obtain a treated support;
• ii. adding said treated support into a fluid medium comprising K2CO3 in the range of 5 wt % to 60 wt % using an incipient wet impregnation method at a temperature in the range of 20° C. to 50° C.;
• and
• iii. allowing K2CO3 to disperse on said treated support for a time period in the range of 10 min to 20 min to form the adsorbent followed by drying at a temperature in the range of 100° C. to 150° C. for at a time period in the range of 10 hours to 12 hours.