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Title: Kinetic Drawbacks of Combining Electrochemical CO 2 Sorbent Reactivation with CO 2 Absorption
Electrochemical CO2 capture approaches, where electrochemical reactions control the sorbent’s CO2 affinity to drive subsequent CO2 absorption/desorption, have gained substantial attention due to their low energy demands compared to temperature-swing approaches. Typically, the process uses separate electrochemical and mass-transfer steps, producing a 4-stage (cathodic/anodic, absorption/desorption) process, but recent work proposed that these energy demands can be further reduced by combining the electrochemical and CO2 mass-transfer reactor units. Here, we used computational models to examine the practical benefit of combining electrochemical sorbent reactivation with CO2 absorption due to this combination’s implicit assumptions about the process rate and therefore, the reactor size and cost. Comparing the minimum energy demand and process time of this combined reactor to those of the separated configuration, we found that the combined absorber can reduce the energy demand by up to 67% but doing so can also increase the process time by several orders of magnitude. In contrast, optimizing the solution chemistry could benefit both the energy demand and process time simultaneously.  more » « less
Award ID(s):
1749207
PAR ID:
10521363
Author(s) / Creator(s):
;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Industrial & Engineering Chemistry Research
Volume:
62
Issue:
46
ISSN:
0888-5885
Page Range / eLocation ID:
19784 to 19800
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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