Carbon Dioxide Absorption in Triethanolamine Aqueous Solutions: Hydrodynamics and Mass Transfer

Abstract

The carbon dioxide absorption process by triethanolamine aqueous solutions was analyzed in a bubble‐column reactor taking into account the chemical reaction mechanism, gas‐liquid interfacial area, and mass transfer rate. A speciation study of this gas‐liquid system was developed by 1H and 13C NMR spectroscopy in order to obtain the reaction mechanism and stoichiometry. The gas‐liquid interfacial area was evaluated considering the variations of bubble size distribution and gas holdup during the operation time. The liquid‐phase mass transfer coefficient was calculated from the carbon dioxide absorption rate data by interfacial area evolution and reaction stoichiometry.

CO2 absorption into N-methyldiethanolamine aqueous-organic solvents

“…The liquid phase was loaded into a double-wall thermostated burette (7) of 2 Á 10 À4 m 3 capacity, connected to the liquid inlet of the reactor. An electronic thermometer Selecta Sensoterm-II (8) provided with Pt1000 (±1 K) allowed the temperature measurement within the liquid phase before feeding the reactor, while the temperature in the thermostatic bath and in the bubble meter was also controlled by means of two mercury thermometers (9).…”

“…The use of tertiary amines in the absorption process of sour gases [8,9] offers several advantages over the most used MEA or DEA. N-methyldiethanolamine is one of the most studied tertiary alkanolamines in literature [10,11] due to a low vapour pressure, low reaction heat with acid gases, high resistance to thermal and chemical degradation and reduced corrosive behavior.…”

Carbon dioxide chemical absorption by solvents based on diamine and amines blend

“…Figure 6 shows the effect of DMAPA concentration on the absorption rate. 20 In the last years, our research group has used 13 C nuclear magnetic resonance to study the reaction intermediates during carbon dioxide capture by amine aqueous solutions. An increase in 3-(dimethylamino)propan-1-amine concentration implies a higher experiment time to reach the saturation.…”

Mass Transfer Analysis of CO2 Capture by PVDF Membrane Contactor and Ionic Liquid

“…However, the regeneration temperature for the CO 2 ‐rich solutions is usually higher than 393 K, which would induce thermal degradation and the volatile loss of solvents . Other problems with these solvents are energy consumption for absorbent regeneration, corrosion of industrial equipment materials, and foam production .…”