pH-swing CO₂

Background and project purpose?
The scope of this project is to investigate an electrochemical pH-swing method to capture CO₂ from aqueous solutions. This technology can be utilized to capture CO₂ from naturally carbonated solutions like seawater and water from closed aquaculture systems as well as to regenerate alkaline solvents (i.e. KOH solutions) used as absorbents in post combustion capture (PCC) or direct air capture (DAC).
What is the project objective?
The objective is to assess the power consumption, CO₂ capture rate and purity of the captured CO₂ of this technology. The performance and degradation of the components of the electrochemical cell will be investigated. The generated results will fill the knowledge gap in electrochemical pH-swing approaches used for carbon dioxide removal (CDR).
What will the project do in terms of activities?
The activities of the project will be the following:
1. Selection of components to be implemented in the electrochemical cell: ion exchange membranes, electrodes, and substrates. Some of the components will be developed by the partners and compared to commercial alternatives.
2. Develop a theoretical description of the system including reactions and flows in the electrochemical cell.
3. Assess and optimize performance of the electrochemical pH-swing system in various carbonated solutions. These include different carbonate concentrations and presence of additional compounds to simulate water from closed aquaculture systems.
Future plans?
The ambition is to use the results of this project as a starting point to increase the maturity of the technology. This will require techno-economical assessments and simulations of operation in real environments. Moreover, the partners will exploit the results as a tool for comparison with alternative CDR technologies.