CO₂ adsorption using water-soluble polyaspartamide

Freeze-drying is one of the promising purification technologies due to its ability to produce outputs with high purity at low energy. This work attempts to improve the adsorption properties of a novel amine adsorbent for CO₂ capture through the use of freeze drying process. Thus, a polyaspartamide (PAA) was produced after freeze-drying process of a polysuccinimide (PSI) synthesized through polycondensation reaction. The synthesized PSI was grafted with a monoethanolamine (MEA), a water-soluble amine, and an ethylenediamine (EDA), then tested for CO₂ capture. The BET analysis showed the enhancement of geometry/structure with the increase of water-soluble amine (MEA) in the PAA. In addition, testing the CO₂ adsorption capacity with pure CO₂ at 1.1 bar and a temperature of 40 °C using a thermogravimetric analyser resulted in increase of CO₂ adsorption capacity as the amount of MEA in PAA increased. The maximum CO₂ adsorbed was 44 mg-CO₂/g at 100% MEA incorporated in PAA, indicating a significant increase from 19 mg-CO₂/g recorded for the crude PSI. Thus, the water soluble PAA could be an effective adsorbent for CO₂ capture via adsorption technology for the reduction of CO₂ emissions in future.