Preliminary screening experiments of carbon dioxide (CO2) absorption into aqueous 35 wt % equivalent potassium carbonate (K2CO3) solution with different additives were performed in a wetted-wall column at 322 K Arginine was found as an effective promoter to enhance the absorption rate in aqueous K2CO3 solution. The effect of arginine concentration and CO2 loading on the absorption rate into carbonate solutions is discussed. The vapor-liquid equilibrium of 35 wt % equivalent K2CO3 with 0-5 wt % arginine was obtained in the temperature range from 323 to 343 K using inert-gas stripping method. Desorption curves of the unpromoted and arginine-promoted carbonate solutions are also discussed.