The Effects of Mass Transfer on the Determination of Gas–Liquid Reaction Kinetics in a Stirred Cell Reactor: In the Case of CO2 Absorption by Aqueous Alkanolamine Solution

Binding organic liquids are a strong base of amidine have been used for CO2 capture. Up to now, there is no known datum on the reaction kinetics of CO2 with 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN). In this paper, Kinetics of reaction between CO2 and DBN/MDEA in 1-Pentanol were performed utilizing the stirred cell reactor with DBN concentration (2 – 2.9 M) and at room temperature. The reaction path was qualified using zwitterion and the termolecular mechanism. From the kinetic datum with DBN concentrations (2 – 2.9 M), it was found that the capturing process happen in a fast reaction system with a second-order reaction kinetics of DBN/MDEA and first order with CO2. In addition, CO2 absorption was achieved using gas – liquid contact system. CO2 absorption rate was (2×10^(-5)-2.8 × 10^(-5) kmol⁄m^2 .sec) at DBN concentration (2 – 2.9 M). Finally, it is known that DBN/MDEA/1-Pentanol/CO2 system is easily switchable and can be used both CO2 capture and for other applications that require rapid change of medium from nonionic to ionic liquid.

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Experimental Study of CO2 Absorption in Potassium Carbonate Solution Promoted by Triethylenetetramine

The Open Chemical Engineering Journal ◽

10.2174/1874123101812010067 ◽

2018 ◽

Vol 12 (1) ◽

pp. 67-79 ◽

Cited By ~ 3

Author(s):

Rouzbeh Ramezani ◽

Saeed Mazinani ◽

Renzo Di Felice

Keyword(s):

Partial Pressure ◽

Potassium Carbonate ◽

Absorption Rate ◽

Low Cost ◽

Total Concentration ◽

Absorption Capacity ◽

Correlated Data ◽

Co2 Absorption ◽

Cell Reactor ◽

Stirred Cell

Background: Separation of CO 2 as the major cause of global warming is essential. In this work, potassium carbonate (K 2 CO 3 ) solution was selected as a base solvent for CO 2 absorption due to its ease of regeneration energy, low cost and low environmental impact. However, the absorption rate of CO 2 with K 2 CO 3 needs to be improved by adding a suitable promoter. Therefore, the performance of CO 2 in K 2 CO 3 solution promoted by triethylenetetramine (TETA) in terms of absorption capacity and absorption rate of CO2 was studied. Method: Experiments were conducted at a total concentration of 2.5 (M) with different TETA mole fractions at temperatures of 303, 313 and 323 K, and CO2 partial pressure up to 30 kPa using a stirred cell reactor. The effect of CO2 partial pressure, temperature and concentration of TETA on absorption capacity and absorption rate of CO2 in K2CO3+TETA solution was discussed in detail. Results: The CO2 loading capacity obtained in this work was compared with monoethanolamine (MEA) and a better performance was observed for K2CO3+TETA solution. In addition, experimental results revealed that the addition of TETA to K2CO3 improved the CO2 reaction rate. Finally, the response surface methodology was employed to correlate the CO2 solubility. It was found that the correlated data are in good agreement with the experiment results. Conclusion: As an overall conclusion, the solution of K2CO3+TETA can be used as a promising absorbent in post combustion CO2 capture processes.

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