Study on absorption of CO_2 into aqueous N-methyldiethanolamine

Among the methods of CO2 separation and capture,the solution absorption is widely used.The absorption of CO2 into aqueous N-methyldiethanolamine(MDEA) was studied under atmospheric pressure.The study result shows that the absorption performances of CO2 can be enhanced effectively by the addition of activator in MDEA.Piperazidine(PZ) is the best activator over others.The optimum CO2 absorption are reached when activator concentration is 0.3 mol/L and MDEA concentration is 3 mol/L.The optimal operation conditions for CO2 adsorption in aqueous MDEA are as follows: MDEA concentration 3 mol/L,PZ concentration 0.6 mol/L,absorption temperature 60 ℃.The performances of CO2 absorption in aqueous MDEA increase with the increase of PZ concentration.The aqueous MDEA can be regenerated very easy at 106 ℃ and the best regeneration time is 3 h.