A Membrane Contactor Enabling Energy-Efficient CO 2 Capture from Point Sources with Deep Eutectic Solvents

Islam, Syed Z.; Arifuzzaman, Md; Rother, Gernot; Bocharova, Vera; Sacci, Robert L.; Jakowski, Jacek; Huang, Jingsong; Ivanov, Ilia Nicolaevich; Bhave, Ramesh R.; Saito, Tomonori; Sholl, David S.

doi:10.1021/acs.iecr.3c00080

DOE OSTI · 1994728

A Membrane Contactor Enabling Energy-Efficient CO 2 Capture from Point Sources with Deep Eutectic Solvents

Islam, Syed Z.·Arifuzzaman, Md·Rother, Gernot·Bocharova, Vera·Sacci, Robert L.·Jakowski, Jacek·Huang, Jingsong·Ivanov, Ilia Nicolaevich·Bhave, Ramesh R.·Saito, Tomonori·Sholl, David S.

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Abstract

We demonstrate a scalable and energy-efficient hollow fiber membrane contactor (HFMC)-based process using a green solvent for CO 2 capture. This process uses a deep eutectic solvent (DES) in an HFMC to provide close interfacial interactions and contact between the DES and CO 2 . This approach overcomes disadvantages associated with direct absorption in DES and could potentially be applied to a variety of solvent-based CO 2 capture methods. Commercial low-cost polymer hollow fiber membranes (e.g., microporous polypropylene) were evaluated for CO 2 capture with reline, a prototypical DES. Single-gas measurements showed that the DES-based polypropylene HFMC can capture and separate CO 2 while rejecting N2. From a mixed gas containing 50 mol % N 2 and 50 mol % CO ν , the DES-based HFMC separated CO 2 with a purity of 96.9 mol %. The effect of several process parameters including solvent flow rate, pressure, and temperature on the CO 2 separation performance was studied. The flux of the recovered CO 2 was 67.43 mmole/m 2 /h at a feed pressure of 4 bar. In situ Fourier transform infrared (FTIR) measurements combined with density functional theory (DFT)-based molecular dynamics simulations revealed that reline absorbs CO 2 by physical absorption without forming a new chemical compound, and CO 2 separation by reline occurs via the pressure swing mechanism. This research provides fundamental insights about physical solvent-based separation processes and a pathway toward practical deployment.

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Islam, Syed Z., Arifuzzaman, Md, Rother, Gernot, Bocharova, Vera, Sacci, Robert L., Jakowski, Jacek, Huang, Jingsong, Ivanov, Ilia Nicolaevich, Bhave, Ramesh R., Saito, Tomonori, Sholl, David S.. 2023-02-22. A Membrane Contactor Enabling Energy-Efficient CO 2 Capture from Point Sources with Deep Eutectic Solvents. https://doi.org/10.1021/acs.iecr.3c00080

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