Vapour-liquid equilibrium study of tertiary amines, single and in blend with 3-(methylamino)propylamine, for post-combustion CO2 capture

Abstract

This work studies the potential of using the tertiary amines 3-dimethylamino-1-propanol (3DMA1P), 3-diethylamino-1-propanol (3DEA1P) and 1-(2hydroxyethyl)pyrrolidine (1-(2HE)PRLD) as an alternative to 2-(diethylamino)ethanol (DEEA) in the blend with 3-(methylamino)propylamine (MAPA). Vapour pressure of the three tertiary amines and vapour-liquid equilibrium (VLE) of the binary mixtures 3DMA1P/H2O, 3DEA1P/H2O and 1-(2HE)PRLD/H2O at T = (353, 363 and 373) K were measured in a modified Swietoslawski ebulliometer. The vapour pressure of the pure amines was fitted to the Antoine equation , and the P-T-x-y data were fitted to NRTL equations. VLE of the CO2 loaded blended amines were measured in the temperature range of T = 313 to 393 K, and speciation data of equilibrated samples at different CO2 loadings were obtained by NMR spectroscopy. The study showed that the tertiary amines 3DMA1P, 3DEA1P and 1-(2HE)PRLD in the binary amine/ H2O system were less volatile than DEEA in aqueous solution. The CO2 loaded blended amines showed comparable VLE behaviour, as well as speciation, and obtained a cyclic capacity higher than that of 30 wt% MEA but similar to most of the blended amines studied in the literature. The overall results indicated that the tertiary amines studied in this work can be used as an alternative to DEEA.

Vapor–Liquid Equilibria Data for 2-Piperidineethanol and 1-(2-Hydroxyethyl)pyrrolidine in Aqueous Solutions and a UNIQUAC Model Representation

“…(2019). 5 The trend of these two sets of data also agrees with a point reported by Astle and Weast (1985), 27 as shown in Figure 1 b.…”

“… Vapor pressure of pure amines (a) 2-PPE and (b) 1-(2HE)PRLD as a function of temperature (○, exp.#1; □, exp#2; Δ, ref ( 5 ); ∗, a normal boiling point of 2-PPE; 12 ∗ , boiling point of 1-(2HE)PRLD at 1.73 kPa; 27 black solid line, a combined fit; red solid line, ref ( 5 )). …”

“…The new data cover a larger range of concentrations, especially at lower concentrations than those reported previously. 5 The low concentration data are crucial in determining the activity coefficient at infinite dilution. The partial pressure of 1-(2HE)PRLD over its aqueous solution is higher than that of 2-PPE at the same conditions.…”

“…We have previously reported screening results of strong bicarbonate-forming solvents for CO 2 capture, 2 characterization of selected solvent systems, 3 and evaluation of process performance using 1-(2-hydroxyethyl)pyrrolidine (1-(2HE)PRLD) and 2-piperidineethanol (2-PPE) 4 for postcombustion CO 2 capture. There is no volatility data for 2-PPE, but some data for 1-(2HE)PRLD are recently reported for temperatures between 353 and 373 K. 5 …”

Novel biphasic amino-functionalized ionic liquid solvent for CO2 capture: kinetics and regeneration heat duty

“…[TETAH][Lys] has five amine groups, all of which could possibly react with CO 2 . Similar to primary or secondary amines, these amino groups react with CO 2 , producing carbamate through the zwitterion mechanism (Andreoni and Pietrucci 2016;Bernhardsen et al 2019;Creamer and Gao 2016;Ramezani et al 2019). Here, the alkyls or active hydrogen atoms are denoted as IL, and [TETAH][Lys] can be abbreviated as IL-NH.…”