The study investigated a key process of CO₂ extraction from seawater using bipolar membrane electrodialysis (BP-ED): seawater acidification. This research examined how temperature, membrane type, current density, energy consumption, and kinetics affect this process. Three seawater temperatures (12, 23, and 33 °C) were selected to represent various geographical scenarios, comparing both homogeneous and heterogeneous bipolar membranes (BPMs) and ion-exchange membranes (IEMs).
Key Results
Critical Variables: The variables that most affect process efficiency are temperature and membrane type. Regardless of the membrane type, higher temperatures led to significant increases in current density and faster acidification kinetics.
Membrane Efficiency: It was determined that homogeneous bipolar membranes can be highly beneficial for the process. Although BPMs showed a resistance 20 to 57 times higher than IEMs, they demonstrated a dominant effect on current density profiles.
pH Optimization: Targeting a pH of 5 instead of 4 resulted in 9.1% to 4.2% faster kinetics, with slightly lower specific energy consumption (SEC) values (1.2–3.4%)
Impact and Publication
The main objective of this work is to provide deep insight for the future design of membranes and to optimize the BP-ED method as a strategy to mitigate climate change through oceanic carbon capture. This scientific article was published in the journal ‘ACS Sustainable Resource Management’ (Volume 2 - Issue 6, 2025).
Read and discover more about the article and its conclusions HERE.
Authors and Institutions:
ESPOL (Ecuador): Priscila Valverde, Ph.D.; Leonardo Gutiérrez, Ph.D.; Jonathan Mendez, Ph.D.(c).
Ghent University (Belgium): Francis Kotoka, Maarten Bossuyt, Emile Cornelissen, Afroditi Kourou, Yi Ouyang y Kevin Van Geem.
FujiFilm Europe B.V. (The Netherlands): Abdulsalam Alhadidi.
This research highlights that the synergy between operating conditions and advanced materials is crucial for making ocean-based carbon capture a reality. By proving that homogeneous bipolar membranes and elevated temperatures significantly boost the efficiency of seawater acidification, this study provides a clear roadmap for reducing the energy footprint of CO₂ extraction. Ultimately, these findings represent a vital step toward scaling sustainable technologies that can effectively protect our oceans and atmosphere, bridging the gap between academic innovation and industrial climate solutions.
