Equilibrium solubility measurement and Kent‐Eisenberg modeling of CO₂ absorption in aqueous mixture of N‐methyldiethanolamine and hexamethylenediamine

Abstract

Vapor‐liquid equilibrium of CO2 in aqueous mixture of hexamethylenediamine (HMDA) and N‐methyldiethanolamine (MDEA) has been investigated using a stirred equilibrium cell set‐up in the temperature and pressure range of 303–333K and 1–100kPa, respectively. Composition of the mixed amine solvents used are (5mass% HMDA+25mass% MDEA), (10 mass% HMDA+20 mass% MDEA), (15mass% HMDA+15mass% MDEA), and (20 mass% HMDA+10 mass% MDEA). Equilibrium solubility data is fitted using the Kent‐Eisenberg thermodynamic model. To fit experimental solubility data with model predicted data, bicarbamate formation and zwitterion deprotonation reaction equilibrium constants of HMDA are regressed as a function of CO2 loading and temperature. Average absolute deviation between experimental and model predicted data is found to be 7.16%. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd.

Density, Viscosity, pH, Heat of Absorption, and CO2 Loading Capacity of Methyldiethanolamine and Potassium Lysinate Blend Solutions

“…The Kent-Eisenberg (KE) model has been extensively used for correlation and prediction of phase equilibria using solubility data due to its simplicity and high speed of computation . For example, Tong et al, Mondal et al., Sema et al, and Chang et al correlated the CO 2 loading capacity of 2-amino-2-methyl-1-propanol (AMP) + PZ, MDEA + HMDA, 4-(diethylamino)-2-butanol (DEAB), diethylenetriamine (DETA) + PZ solutions using the KE model. In this model, it assumes that the nonidealities represented by activity coefficients are included in the equilibrium constants .…”

Experimental measurements and modelling of CO2 solubility in aqueous mixtures of benzylamine and N‐(2‐aminoethyl) ethanolamine

“…Equilibrium constants (K 5 and K 7 ) of monocarbamate formation reaction of BZA and AEEA are regressed as a function temperature and CO 2 loading to fit the experimental data with KE model expression. Generalized reduced gradient nonlinear optimization technique is adopted for error minimization between the experimental and model predicted solubility data. The objective function used in this model is described in Equation .…”

“…Heat of absorption value of AEEA (~81.37 kJ/mol CO 2 at 0.101 mol CO 2 /mol amine and 40°C) is similar to MEA (~81.98 kJ/mol CO 2 at 0.124 mol CO 2 /mol amine and 40°C), but AEEA has higher loading capacity and low vapor pressure compared with MEA . Although judicious blending of two or more amines may improve the absorption capacity, absorption rate and reduce the solvent regeneration energy by reducing the resultant value of heat of absorption, little or no work has been reported on the solubility of CO 2 in an aqueous mixture of BZA with second amine component. In this study, the CO 2 solubility data in an aqueous mixture of BZA and AEEA are generated at the temperature range of 313.15 to 333.15 K over a partial pressure range up to 219 kPa.…”

Enrichment in CO2 Absorption by 2-Methyl Piperazine-Activated Tertiary Amines, Physical Solvents, and Ionic Liquid Systems

“…Other amine activators which have been studied and proposed for the said purpose are bis (3-aminopropyl) amine (APA), hexamethylenediamine, and triethylenetetramine. 15 − 18 One of the PZ derivatives, viz., 2-methyl piperazine (2-MPZ), is explored in the present study for CO 2 absorption. A brief literature review of the selected solvents is discussed in the subsequent text.…”