Mixture Absorption System of Monoethanolamine−Triethylene Glycol for CO₂ Capture

Abstract

In this paper, a mixture system without water but composed of monoethanolamine (MEA) and triethylene glycol (TEG) is designed for CO 2 capture. The solubility of CO 2 in pure TEG and MEA-TEG solutions is determined, respectively, showing that the solubility of CO 2 in TEG is generally consistent with Henry's Law and the value is higher than that in water. The solubility of CO 2 in MEA-TEG solutions significantly increases with the increase of MEA, showing the characteristics of chemical reaction absorption. The absorption mechanism study shows that TEG does not act as a reaction agent. There is only one reaction between CO 2 and MEA. The absence of water in the new system leads to the absence of dissociation of protonated MEA and formation of carbamate (MEACOO -). This is much different from the MEA-water system. A mathematical model is also developed for predicting the solubility of CO 2 in the new system. The results show that the absorption and desorption can be realized at relatively lower temperatures (lower than 353.15 K), which may provide advancement in two aspects: low energy consumption with less solvent evaporation and avoidance of MEA's degradation caused by high-temperature operation.

An investigation of the role of N-methyl-diethanolamine in non-aqueous solution for CO2 capture process using 13C NMR spectroscopy

“…At present, solution of blended amines has been widely studied because it combines the favorable characteristics of different alkanolamines while suppressing their unfavorable characteristics (Aroonwilas and Veawab, 2004). However, energy consumption has been demonstrated to be the key factor reducing the efficiency of power plants by many researchers (Chakma, 1995;Oexmann and Kather, 2010;Tan et al, 2011). Recently, non-aqueous solutions have been extensively investigated using organic solvents, such as methanol, ethanol, ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), diethylene glycol monomethyl ether (DGME), Nmethyl-2-pyrrolidone (NMP) and tributyl phosphate (TBP) (Leites, 1998;Jou et al, 2000;Park et al, 2005Park et al, , 2006aUsubharatana and Tontiwachwuthikul, 2009;Hwang et al, 2010;Tan et al, 2011), which provide significant advantages as for reducing solvent decomposition at high temperature and saving water evaporation energy in the CO 2 stripping process (Barzagli et al, 2013Yu et al, 2013.…”

On the CO2 Capture in Water-Free Monoethanolamine Solution: An ab Initio Molecular Dynamics Study

“…12 Other amine-based solutions suffer from similar energy deficiency issues. Therefore, reducing water content in the aqueous solutions of the sorbents could potentially enhance the overall energy efficiency substantially for the amine based CO 2 separation processes as suggested by several CO 2 separation research teams.…”

Determination of kinetics of CO2 absorption in solutions of 2‐amino‐2‐methyl‐1‐propanol using a microfluidic technique

“…There is a trade-off between capital costs and energy requirements. In our previous work, 24 we achieved a high masstransfer efficiency of gas absorption into solution with high viscosity using a microfluidic device based on membrane contactor. With the development of high efficient absorption equipment for the relatively high viscosity system, both low energy consumption and low capital cost may be reached.…”