Phase change absorbents have recently drawn increasing attention due to the potential of for low energy-consuming CO₂ capture. When forming two phases after CO₂ absorption, only the CO₂-rich phase is heated in the desorption process thus reducing the sensible heat. In this work, five amine and three alcohol blends were used to investigate their phase change behavior after reacting with CO₂. Phase separation could easily occur for DETA/alcohol/water combinations after CO₂ absorption, which was confirmed by the large difference of the solvation free energy in alcohol and in water (i.e. DETA-CO₂ has 12.5 kcal/mol ΔGsol in 1-propanol less than that in water). The optimization of the DETA/1-propanol/H₂O solution was confirmed to be 30% DETA + 30% 1-propanol + 40% H₂O (D30P30H40). It was found that above 90% of CO₂ loading was enriched in lower phase. ¹³C NMR spectrum indicated that carbamate and bicarbonate was formed in lower phase and 1-propanol acted as a good physical solvent to trigger phase separation and facilitate the reaction between amine and CO₂.