Experimental measurement and modeling study on CO 2 equilibrium solubility, density and viscosity for 1-dimethylamino-2-propanol (1DMA2P) solution Morteza Afkhamipour, Masoud Mofarahi * Department of Chemical Engineering, Faculty of Petroleum, Gas and Petrochemical Engineering, Persian Gulf University, Bushehr 7516913798, Iran article info Article history: Received 11 May 2017 Received in revised form 12 September 2017 Accepted 20 September 2017 Available online 27 October 2017 Keywords: CO 2 solubility Viscosity Density 1DMA2P Thermodynamic models abstract In this study, new experimental data of CO 2 equilibrium solubility for an aqueous solution of 1DMA2P, a novel ternary amine, are presented over a CO 2 partial pressure range of 3e168 kPa, at different con- centrations of 1DMA2P (2, 3 and 4 M), and in a temperature range of 298.15e333.15 K. Besides, new experimental data of viscosity and density are reported in a concentration range from 20 wt% up to pure 1DMA2P, in a temperature range of 298.15e333.15 K, and in atmospheric pressure. CO 2 equilibrium solubility data were predicted by DeshmukheMather (D-M) thermodynamic model. From the experi- mental data of density and viscosity, thermodynamic properties including the thermal expansion coef- ficient (a p ), excess molar volume (V E ), viscosity deviation (Dh), activation molar enthalpy (DH), activation molar entropy (DS), and activation molar Gibbs free energy (DG) were obtained. We have modeled and predicted the experimental data of viscosity based on Eyring's theory and nonrandom two-liquid (NRTL) and Wilson models. The results showed that the Eyring-Wilson model predicts the experimental vis- cosity data better than Eyring-NRTL. For CO 2 equilibrium solubility, D-M model gave a good prediction with an absolute average relative deviation of 2.64%. © 2017 Elsevier B.V. All rights reserved. 1. Introduction The CO 2 solubility, density, and viscosity of amine solutions are important properties for the designing and simulation of absorption-desorption units, for example, in the field of CO 2 cap- ture or gas sweetening processes [1,2]. Well-known amine solu- tions such as monoethanolamine (MEA), diethanolamine (DEA), and methyldiethanolamine (MDEA) have been widely used in amine plant units [3]. However, these amines have some draw- backs; for example, MEA and DEA consume high energy for their regeneration (about 70% of plant cost), increase corrosion rate, and increase thermal and oxidation degradation [4]. MDEA as a ternary amine has a low reaction rate with CO 2 in comparison with MEA and DEA, but it consumes lower energy than MEA and DEA for its regeneration. Therefore, research activities are ongoing to find the ideal amine solution to overcome the mentioned problems [5]. In general, a ternary amine requires low energy for its regeneration, which can reduce the cost of the amine plant. Recently, Chowdhury, et al. [6] have evaluated 24 kinds of novel tertiary amines, and they found that 7 amines have good potential for application in CO 2 removal processes. Among these amines, 1-dimethylamino-2- propanol (1DMA2P), compared to MDEA, showed good potential for absorption of CO 2 because of its high absorption rate and high equilibrium loading [7,8]. There are many studies about CO 2 solu- bility, density, and viscosity of amine solutions in literature, and the studies are associated with experimental and theoretical subjects [9e12]. We have only reviewed some recently studies related to 1DMA2P solution as follows: Chowdhury et al. [13] have measured the densities of 1DMA2P at different mole fractions and tempera- ture ranges from 303.15 K to 323.15 K. They correlated the V E by applying the RedlicheKister equation; Idris et al. [14] have measured and correlated the new experimental data of density of unloaded and loaded with CO 2 for 1DMA2P solution at different weight fractions from 10 wt % to pure 1DMA2P and at temperature ranging from 298.15 K to 353.15 K. They correlated the experi- mental data by using the RedlicheKister equation. In associated with CO 2 equilibrium solubility, Liu, et al. [8] have presented the equilibrium CO 2 solubility data for 1DMA2P concentrations of 1, 2 and 5 M within the temperature range of 298.15e333.15 K and the * Corresponding author. E-mail address: mofarahi@pgu.ac.ir (M. Mofarahi). Contents lists available at ScienceDirect Fluid Phase Equilibria journal homepage: www.elsevier.com/locate/fluid https://doi.org/10.1016/j.fluid.2017.09.019 0378-3812/© 2017 Elsevier B.V. All rights reserved. Fluid Phase Equilibria 457 (2018) 38e51