Abstract
Increasing CO2 emissions from using fossil fuels and the resulting greenhouse effect have received extensive concerns, and the reduction of CO2 has become the global trend. One of the most important CO2 capture methods is the chemical absorption, which are widely applied to industrial plants. Amine-based solutions are considered as common absorbents to effectively capture CO2. Although these absorbents have high absorption reactivity, there are certain serious problems such as high energy cost during the regeneration process. An ideal absorbent should have high cyclic loading and low solvent consumption amount without suffering precipitation. Low regeneration energy penalty is the most important economic factor in a CO2 capture process. In this study, 30wt% monoethanolamine (MEA) solution was used as a basic standard to evaluate CO2 capture performance of new absorbents. Cations (tetramethylammonium [N1111], tetraethylammonium [N2222], methyl-triethylammonium[N2221], Methyl-tributylammonium [N1444], and (1-Butyl)triethylammonium [N2224]) and anions (L-Alanine, β-Alanine, Glycine, Sarcosine, and L-proline) were combined to yield 25 wt% tetra-alkyl-ammonium amino acid ionic liquid aqueous solutions, and then CO2 absorption and regeneration performances of new absorbents were investigated. The results show that [N1444][L- Alanine] have both high absorption and desorption efficiency without precipitation problem. Regeneration energy penalty of this absorbent is lower than heat of amine-based solutions. Thus, [N1444][L- Alanine] can be considered as a potential candidate for CO2 capture.