In this study, vapour-liquid equilibrium of carbon dioxide in aqueous potassium lysinate (LysK) with separate blends of piperazine (PZ) and 2-amino-2-methyl-1-propanol (AMP) were studied for a wide range of temperature (303.15 - 343.15K), pressure (450 - 4100kPa) and solvent concentration (1 - 3 molar). The effect of promoters such as AMP and PZ on the carbon dioxide absorption capacity of LysK was investigated. Results show that carbon dioxide loading capacity has an inverse relation with temperature and solution concentration and the highest loading takes place at highest pressure. Significantly, LysK-AMP gave a maximum CO2 loading value of 3.62 moles as compared to LysK-PZ of only 1.49 moles, both at highest pressure of approximately 4000kPa. Thus AMP is proven to be more effective promoter to enhance carbon dioxide absorption than PZ. © 2018 Author(s).