Modelling the fluid phase behaviour of aqueous mixtures of multifunctional alkanolamines and carbon dioxide using transferable parameters with the SAFT-VR approach

Abstract

Among the many applications that alkanolamines find in industry, carbon dioxide (CO 2 ) capture from large stationary sources is becoming most relevant. Aqueous mixtures of amines and CO 2 have a complex behaviour, characterised by extensive hydrogen bonding and other types of chemical reactions. An implicit treatment of the key reactions via appropriate association schemes has been shown to provide a promising physical basis for the modelling of these systems. Here, we introduce association models for use with SAFT-VR for some of the more promising multifunctional alkanolamines in the context of CO 2 capture: monoethanolamine (MEA), 2-amino-2-methyl-1-propanol (AMP), diethanolamine (DEA) and methyldiethanolamine (MDEA), and their mixtures with H 2 O and CO 2 . A revised model of the MEA + H 2 O + CO 2 mixture is also presented with an extension to high temperature. Excellent predictive capabilities are demonstrated for pure components and binary aqueous mixtures. Good overall results are also obtained for the ternary aqueous mixtures of alkanolamines and CO 2 , particulary for DEA and MDEA. Furthermore, the degree of speciation is successfully predicted for the MEA + H 2 O + CO 2 mixture. Since only a limited number of parameters need to be estimated from vapour-liquid equilibrium data, the ternary SAFT-VR reaction-implicit models developed in this work offer a useful initial assessment of the different solvents and blends.2

Off-design point modelling of a 420 MW CCGT power plant integrated with an amine-based post-combustion CO2 capture and compression process

“…The SAFT-VR equation-of-state (Gil-Villegas et al, 1997 andGalindo, Davies &Jackson, 1998) was used to describe the thermophysical properties of the MEAsolvent used in the PCC plant model using the approach described in our previous work (Mac Dowell et al, 2009, Mac Dowell et al, 2012and Rodriguez et al, 2012.…”

Size distribution of associated clusters in liquid alcohols: Interpretation of simulation results in the frame of SAFT approach

“…Also the carbon capture using aminoalcohols represents a perspective area in which the association is involved. 54,55 In both these examples, the correct treatment of the association is crucial to obtain good thermodynamic description. In the first case because the bio-oils are mixtures of acceptor rich organic compound (esters, ketones) with water.…”

Computer-aided molecular design and selection of CO2 capture solvents based on thermodynamics, reactivity and sustainability

“…At 97 and n-alkylamines 98 , and further extended by Rodriguez et al 99 using the SAFT-VR EoS applied to various aqueous mixtures of alkanolamines and carbon dioxide. To enhance the predictive capabilities of this approach, models to predict the phase behaviour and thermophysical properties of aqueous alkanolamine mixtures with CO 2 using the GC formalism embedded within the SAFT-γ SW framework 67,68 have been proposed [69][70][71] .…”