Equilibrium Solubility of CO₂ in Aqueous Blend of 2-(Diethylamine)ethanol and 2-(2-Aminoethylamine)ethanol

Abstract

New experimental CO 2 solubility data at equilibrium in an aqueous blend of 2-(diethylamino)ethanol (DEEA) and (2-aminoethyl) ethanolamine (AEEA) have been illustrated for the concentration of CO 2 in the inlet gas stream ranging from 10.132 to 20.265 kPa and aqueous amine blend temperature ranging from 303.14 to 333.14 K. Total concentrations of aqueous blend were taken in the range of 1.0−3.0 kmol/m 3 and mole fraction of AEEA in total amine blend in the range of 0.02−0.20. Experiments were carried out in a semibatch operated laboratory scale gas−liquid bubbling absorber, and analysis of liquid phase CO 2 as a saturated liquid was done by titration method. The equilibrium CO 2 solubility in DEEA + AEEA blend was found to be a maximum at the value of 0.843 mol CO 2 /mol amine with AEEA mole fraction in total amine of 0.2 at 1 kmol/m 3 total concentration of amine mixture and 303.14 K. New solubility data of CO 2 in the present work was compared with existing literature data. An empirical correlation was developed from experimental CO 2 solubility data as a function operating variables in the studied range.

Equilibrium Solubility Measurement and Modeling of CO2 Absorption in Aqueous Blend of 2-(Diethyl amino) Ethanol and Ethylenediamine

“…The equilibrium CO 2 solubility in DEEA+EDA solution was measured with the help of the little-modified apparatus used in the present work as similar to our previous work . The whole experimental apparatus can be divided into three sections, including the feed gas stream, absorber, and gas analysis section.…”

“…Currently, the absorption process using an amine aqueous solution is widely used in the purification of gases and CO 2 capture process. , The commonly used amine absorbents are monoethanolamine (MEA), diethanolamine (DEA), methyl diethanolamine (MDEA), 2-amino-2-methyl-1-propanol (AMP), and polyamines (PZ) . Several researchers measured the CO 2 capture performance of different tertiary amines such as 2-(dimethylamino)­ethanol (DMEA), 2-(diethylamino)­ethanol (DEEA), 1-dimethylamino-2-propanol (DMAP-12),3-dimethylamino-1-propanol (DMAP-31), 4-((2 hydroxyethyl)­(ethyl)­amino)-2-butanol (HEEAB), 1-(2 hydroxyethyl)­pyrrolidine (1-(2-HE)­PRLD), 4-(dipropylamino)-2-butanol (DPAB), 3-diethylamino-1,2-propanediol (DE-1,2-PD), 4-((2-hydroxyethyl)­(methyl)­amino)-2-butanol (HEMAB), 1-(2-hydroxyethyl)-piperidine (1-(2-HE)­PP), 4-(dimethylamino)-2-butanol (DMAB), 2-(2-(dimethylamino) ethoxy) ethanol (DMAEOE), 1,2-bis (dimethyl amino) ethane (TEMED), methyl-4-morpholine, pyridine, ethyldiethanolamine (EDEA), and butyldiethanolamine (BDEA) at various operating conditions at lab-scale. − Again, various authors studied the absorption–desorption performance of polyamines such as ethylenediamine (EDA), 1,3-diaminopropane (DAP), N -methylpropane-1,3-diamine (MAPA), 3-(dimethylamino)­propylamine (DMAPA), N -methylethylenediamine (MEDA), 2-dimethylaminoethylamine (DMAEA), diethylenetriamine (DETA), triethylenetetramine (TETA), and tetraethylenepentamine (TEPA) at lab-scale. − Among these, MEA is most widely used in the CO 2 capture process because of its high CO 2 absorption capacity, fast reaction/absorption rate, and low solvent cost . Unfortunately, it requires high energy in the regeneration process which has led to interest in the development of an alternative solvent as well as a blended solvent to improve the CO 2 capture performance by compensating for the drawbacks of individual solvents.…”

“…In order to improve the DEEA absorbance for CO 2 capture, most of the researchers used various types of amine additives as activator or promoter. However, they have studied DEEA with different additives such as MEA, ,, MAPA, − AEEA, HMDA, and PZ, − to improve its capture performance, with evaluations of the solubility, absorption capacity, absorption heat, absorption rate, reaction rate, and absorption coefficient, etc. Diamine EDA shows a good absorption performance due to its high absorption capacity, high absorption/reaction rate, and low degradation tendency.…”

“…The equilibrium CO 2 solubility in DEEA+EDA solution was measured with the help of the little-modified apparatus used in the present work as similar to our previous work. 19 The whole experimental apparatus can be divided into three sections, including the feed gas stream, absorber, and gas analysis section. The measurement of CO 2 solubility in aqueous amine blend was performed in a laboratory scale bubbling absorber by a continuous flow of the simulated gas streams of CO 2 .…”

Experimental Data and Modeling for Viscosity and Refractive Index of Aqueous Mixtures with 2-(Methylamino)ethanol (MAE) and Aminoethylethanolamine (AEEA)

“…AEEA can absorb 2 mol of CO 2 and shows high CO 2 cyclic capacity, high values of second-order reaction rate, and lower regeneration energy. Thus, it has been reported as a very efficient activator in amine blend for CO 2 absorption and shows high CO 2 absorption capacity. − To the best of our knowledge, viscosity and refractive index data have not been correlated with the composition of aqueous blend of MAE and AEEA and temperature in the published literature.…”