Measurement of vapour-liquid equilibrium and e-NRTL model development of CO2 absorption in aqueous dipropylenetriamine.
Neha Kumari Agarwal, Bikash Kumar Mondal, Amar Nath Samanta
Environmental science and pollution research international April 1, 2021 DOI: 10.1007/s11356-020-12019-w (opens in new tab) via PubMed
Summary
AI-generated from the abstractAqueous dipropylenetriamine (DPTA) captures carbon dioxide more effectively than conventional solvents such as monoethanolamine, 2-amino-2-methyl-1-propanol, and N-methyldiethanolamine, as well as newer polyamine solvents like aminoethylethanolamine, piperazine, and hexamethylenediamine. Vapour-liquid equilibrium data for CO₂ in DPTA solutions were measured at temperatures from 313 to 333 K and pressures from 1 to 100 kPa, with DPTA concentrations of 5 to 15 mass%. The electrolyte non-random two-liquid (e-NRTL) model, fitted using Aspen Plus data regression, predicted the experimental data with an average absolute deviation of 22.3%. The model also estimated solvent capacity, liquid-phase speciation, and heat of CO₂ absorption.
Study at a glance
| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | CO₂ in aqueous dipropylenetriamine (DPTA) solutions |
| Keywords | Aspen plus Carbon dioxide co2 Dipropylenetriamine dpta Vapour-liquid equilibrium vle E-nrtl |
| Citations | 8 |
| Key finding | Aqueous DPTA shows higher CO₂ loading capacity than conventional and several polyamine solvents, and the e-NRTL model correlates the VLE data with an average absolute deviation of 22.3%. |
Abstract
Vapour-liquid equilibrium (VLE) of CO2 in aqueous dipropylenetriamine (DPTA) is investigated experimentally using a stirred equilibrium cell setup. Equilibrium solubility of CO2 is measured in the temperature and pressure range of (313-333) K and (1-100) kPa respectively. Composition of aqueous DPTA solvent used for the absorption study is in the range of (5-15) mass%. Experimental data shows higher CO2 loading capacity of this solvent compared to conventional solvents like monoethanolamine (MEA), 2-amino-2-methyl-1-propanol (AMP), and N-methyldiethanolamine (MDEA) as well as recently developed polyamine solvents like aminoethylethanolamine (AEEA), piperazine (PZ), and hexamethylenediamine (HMDA). Experimental VLE data is then correlated using the electrolyte non-random two-liquid (e-NRTL) theory which is an activity coefficient-based model for the electrolyte system. Data regression system (DRS) in Aspen Plus® (V8.8) is employed to fit the e-NRTL model equation with the experimental data by regressing the model parameters. Model-predicted data is found to be in good agreement with the experimental VLE data with an average absolute deviation of 22.3%. Performance of aqueous DPTA solvent is also analysed by predicting solvent capacity, equilibrium liquid-phase speciation, and heat of CO2 absorption using the newly developed e-NRTL model for the investigated system.