Study On The Absorption Performance Of CO₂ In DEA Promoted K₂CO₃ Solution At High Temperatures

The absorption capacity of CO₂ and CO₂ loading in diethanolamine?DEA?promoted potassium carbonate?K₂CO₃?aqueous solutions were measured at normal pressure.The temperatures ranged from 343.2K to 363.2K.The mass fractions of K₂CO₃ and DEA respectively ranged from 0.35 to 0.40 and 0 to 0.02.The absorption rates were determined by using the experimental data of the time-dependent absorption capacities.The effects of temperature,mass fraction of DEA and mass fraction of K₂CO₃ on the absorption capacity,CO₂ loading and absorption rate were illustrated.Our results show that:?1?The absorption capacity of CO₂ respectively increases and decreases with increasing mass fraction of absorbent and increasing temperature,while the CO₂ loading decreases with the increase of both mass fraction of absorbent and increasing temperature;?2?At high temperatures,DEA can significantly promote the absorption rate of CO₂.When the mass fractions of DEA are of small values,the absorption rate of CO₂ in DEA promoted K₂CO₃ aqueous solutions gets 3-4 times as that in K₂CO₃ aqueous solutions;?3?The absorption rate of CO₂ increases with increasing temperature and increasing solution concentration;?4?At given mass fraction of K₂CO₃?0.35?,the optimal mass fractions of DEA are around 0.01-0.02,under which both high absorption rate and high CO₂ loading can be achieved simultaneously.