CO2 포집을 위한 흡수 공정에서의 흡수제 재생에너지를 줄이기 위해 본 연구에서는 CO2와 반응하여 주 흡수제 역

할을 하는 1차 및 2차 아민과 상분리를 유도하는 부 흡수제 역할인 3차 아민을 도입한 2종 아민 상분리 흡수제를 제

안하였다. CO2 흡수 전과 후 흡수제의 혼화도에 따라 흡수제를 3가지 유형으로 분류하고 이를 옥탄올-물 분배계수

(logP)를 이용하여 해석하였다. 3차 아민의 logP 값이 0보다 작은 경우 단일 상으로 존재하고, 3차 아민의 logP 값이

0보다 큰 경우에는 CO2 흡수 전에는 단일 상을 형성하지만, CO2 흡수 후에는 흡수제와의 반응으로 생성된 카바메이

트의 용해도 제한으로 인해 액-액 상분리가 발생하였다. CO2 농축효과와 흡수 평형에 도달하는 속도를 고려하여 CO2

흡수 후에 상분리가 발생하는 2종 아민 상분리 흡수제로 MAPA(3-(methylamino)propylamine)/TMPDA(N,N,N',N'-

tetramethyl-1,3-propanediamine)와 AEEA(2-(2-aminoethylamino)ethanol)/TMPDA (N,N,N',N'-tetramethyl-1,3-propanediamine)

흡수제를 선정하였고 이들 흡수제의 하부상의 로딩값은 각각 220 gCO2/Lsolvent, 274 gCO2/Lsolvent로 30 wt% MEA

흡수제의 로딩값의 약 2배 이상을 보였다.

In this study, to reduce the regeneration energy of absorbents in the CO2 capture process, a two-component

amine phase-separation absorbent was proposed, incorporating primary and secondary amines, which serve as the main

absorbents reacting with CO2, and tertiary amines, which function as auxiliary absorbents inducing phase separation.

The absorbents were classified into three types based on their miscibility before and after CO2 absorption, and this was

analyzed using the octanol-water partition coefficient (logP). When the logP value of the tertiary amine is less than 0, it

exists as a single phase. When the logP value is greater than 0, it forms a single phase before CO2 absorption, but after

CO2 absorption, liquid-liquid phase separation occurs due to the limited solubility of the carbamate, a reaction product

formed with the absorbent. Considering the CO2 concentration effect and the rate of reaching absorption equilibrium,

two types of two-component amine phase-separation absorbents, MAPA(3-(methylamino)propylamine)/TMPDA

(N,N,N',N'-tetramethyl–1,3-propanediamine) and AEEA(2-2-aminoethylamino)ethanol)/TMPDA(N,N,N',N'-tetramethyl-1,3-

propanediamine) were selected. The loading values of the lower phase in these absorbents were 220 gCO2/Lsolvent and

274 gCO2/Lsolvent, respectively, which were more than twice the loading value of the 30 wt% MEA absorbent.

CO2 capture, Regeneration energy, Biphasic solvent, MAPA, AEEA, TMPDA

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