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Several carbon sequestration technologies have been proposed to utilize carbon dioxide (CO2) to produce energy and chemical compounds. However, feasible technologies have not been adopted due to the low efficiency conversion rate and high-energy requirements. Process intensification increases the process productivity and efficiency by combining chemical reactions and separation operations. In this work, we present a model of a chemical-electrochemical cyclical process that can capture carbon dioxide as a bicarbonate salt. The proposed process also produces hydrogen and electrical energy. Carbon capture is enhanced by the reaction at the cathode that displaces the equilibrium into bicarbonate production. Literature data show that the cyclic process can produce stable operation for long times by preserving ionic balance using a suitable ionic membrane that regulates ionic flows between the two half-cells. Numerical simulations have validated the proof of concept. The proposed process could serve as a novel CO2 sequestration technology while producing electrical energy and hydrogen.
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Building Subtraction Operators and Controllers Via Molecular Sequestration
We show how subtraction can be performed via a simple chemical reaction network that includes molecular sequestration. The network computes the difference between the production rate parameters of the two mutually sequestering species. We benefit from introducing a simple change of variables, that facilitates the derivation of an approximate solution for the differential equations modeling the chemical reaction network, under a time scale separation assumption that is valid when the sequestration rate parameter is sufficiently fast. Our main result is that we provide simple expressions confirming that temporal subtraction occurs when the inputs are constant or time varying. Through simulations, we discuss two sequestration-based architectures for feedback control in light of the subtraction operations they perform.
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- Award ID(s):
- 2107483
- PAR ID:
- 10465831
- Editor(s):
- Dabbene, Fabrizio
- Publisher / Repository:
- IEEE Control Systems Letters
- Date Published:
- Journal Name:
- IEEE Control Systems Letters
- Edition / Version:
- 1
- Volume:
- 7
- ISSN:
- 2475-1456
- Page Range / eLocation ID:
- 1 to 1
- Subject(s) / Keyword(s):
- Molecular sequestration, chemical reactions, molecular controllers, biological systems.
- Format(s):
- Medium: X Size: 0.9 Other: pdf
- Size(s):
- 0.9
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/LCSYS.2023.3294690
