Energetics of electrochemically mediated amine regeneration process for flue gas CO₂ capture

Journal Article · Thu Jan 10 00:00:00 EST 2019 · International Journal of Greenhouse Gas Control

DOI:https://doi.org/10.1016/j.ijggc.2018.12.028· OSTI ID:1489146

Wang, Miao ^[1]; Hariharan, Subrahmaniam ^[2]; Shaw, Ryan A. ^[2]; Hatton, T. Alan ^[2]

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1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); MIT-Department of Chemical Engineering
2. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

The electrochemically mediated amine regeneration (EMAR) process presents an alternative route to the conventional thermal regeneration of amines for carbon capture from a flue gas source. In this study, chemical and electrochemical measurements were performed to validate the speciation and activity coefficient models that describe the solution thermodynamics. Electrochemical kinetics and efficiencies were identified and process level energetic calculations were performed using these validated models to understand the effects of various operating parameters on the energy demand for CO₂ capture. An isothermal EMAR process requires about 52 kJe/molCO₂, and the net energy demand can be reduced to about 37 kJe/molCO₂ if waste heat is available at temperatures below 90 °C. The EMAR process is able to desorb CO₂ at pressures up to 20 bar with negligible additional energy penalty. These results suggest that the EMAR process is competitive with the conventional thermally regenerated amine processes. Preliminary assessments also indicate the solvent fomulation with NaCl requires less electric energy among other conventional supporting salt candidates (e.g. Na₂SO₄) for electrolytic processes. Furthermore, advanced process designs, process optimization, and the identification of improved solvents may offer the potential to further reduce the energy demand for CO₂ capture.

• Research Organization: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
• Sponsoring Organization: USDOE; USDOE Office of Fossil Energy (FE), Clean Coal and Carbon Management
• Grant/Contract Number: FE0026489
• OSTI ID: 1489146
• Alternate ID(s): OSTI ID: 1646886; OSTI ID: 1496442
• Journal Information: International Journal of Greenhouse Gas Control, Journal Name: International Journal of Greenhouse Gas Control Journal Issue: C Vol. 82; ISSN 1750-5836
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

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