Diamine-based water-lean absorbent for CO2 capture: Performance and molecular dynamics insights

Zhenzhen Zhang, Yucong Ge, Xunxuan Heng, Li Yang, Zeyu Wang, Fang Liu, Xiao Yang and Kunlei Liu

Energy, 2025, vol. 324, issue C

Abstract: Achieving carbon neutrality requires efficient, energy-saving carbon dioxide capture technologies. Conventional monoethanolamine (MEA) solutions suffer from high energy consumption, volatility, and degradation. This study develops a diamine-based water-lean solvent, consisting of 2-ethylhexylamine (EHA), N,N-dimethylethylenediamine (DMEDA), and dimethyl sulfoxide (DMSO), and evaluates its CO2 capture performance. The EHA-based solvent achieved a CO2 absorption capacity of 3.7 mol/kg and a rate of 1.83 mol/kg·s, outperforming Aminoethyl Ethanolamine (AEEA)-based and MEA-H2O solutions. Regeneration energy was reduced by 65 %, with activation energies of 31.2 kJ/mol (EHA) and 33.15 kJ/mol (AEEA). Molecular dynamics (MD) simulations revealed enhanced CO2 diffusion and solvent stability due to optimized bond length distribution. DMSO improved mass transfer, mitigated viscosity resistance, and stabilized carbamate formation. Fourier transform infrared (FTIR) spectroscopy confirmed that water-lean systems favored carbamate selectivity over bicarbonate formation. These findings demonstrate the industrial potential of EHA-based solvents for high-emission scenarios, offering reduced energy use and improved process stability. This work provides a framework for designing efficient, low-viscosity solvents for sustainable CO2 capture.

Keywords: CO2 capture; Diamine-based solvent; Water-lean absorbents; Absorption performance; Molecular dynamics simulations (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544225016810
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:324:y:2025:i:c:s0360544225016810

DOI: 10.1016/j.energy.2025.136039

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().