A group of researchers from the Shenzhen Institutes of Advanced Technology and the University of Electronic Science and Technology of China succeeded in designing the first reactor capable of converting dissolved carbon dioxide in seawater into succinic acid, a base molecule for manufacturing biodegradable plastics such as PBS (polybutylene succinate).
The discovery, made on the coast of Shezem and published in the scientific journal Nature Catalysis, demonstrates that CO₂ can cease to be a climate problem in the oceans and become a sustainable raw material.
How the reactor works
The key lies in the combination of electrochemical technology and biotechnology:
- Seawater passes through a five-chamber electrochemical reactor.
- An electric current separates the water molecules, generating protons that acidify one chamber and release CO₂ in gaseous form.
- That gas is channeled into a second module, where a bismuth catalyst reduces CO₂ to formic acid, an energy-rich intermediate substance.
- Finally, a modified marine bacterium, Vibrio natriegens, ferments the formic acid and transforms it into succinic acid, a key compound for producing biodegradable plastics.
Promising results
The system managed to operate continuously for more than 530 hours, using real water from the Shenzhen Bay.
- 70% efficiency in carbon capture.
- Estimated cost of 200 euros per ton of processed CO₂, placing it among the most competitive carbon reuse technologies.
Moreover, thanks to its modular design, the reactor can be adapted to produce other industrial compounds such as lactic acid, alanine, or 1,4-butanediol, adjusting production according to market demand.
A marine biofactory for the circular economy
This advance not only reduces atmospheric CO₂, but also takes advantage of the carbon already dissolved in the oceans, which store 150 times more than the Earth’s atmosphere.
Transforming that excess into useful materials contributes to:
- Alleviating marine acidification.
- Creating a circular economy, where carbon ceases to be waste and becomes a resource.
- Promoting a new generation of sustainable marine biofactories.
Oceanic carbon capture: why it is crucial
The ocean is the main natural carbon sink and regulates the global climate:
- Climate regulation: absorbs heat and stabilizes the Earth’s temperature.
- Mitigation of global warming: captures a large part of human CO₂ emissions.
- CO₂ absorption: it dissolves in water or is captured by marine plants and phytoplankton.
- Carbon cycle: maintains the balance of gases in the atmosphere and on Earth.
Threats and challenges
- Ocean acidification: excessive CO₂ absorption damages marine ecosystems and key species such as shellfish.
- Human impact: deforestation and land-use change reduce the capacity of natural sinks, increasing the risk of them becoming carbon sources.
Path to climate neutrality
The reactor designed in China represents a paradigm shift in carbon capture. By using the ocean as an active source of CO₂ and combining it with marine renewable energies —such as wind or tidal—, this technology could operate with an almost zero footprint and offer a real pathway to climate neutrality.
The invention not only opens new possibilities for the biodegradable plastics industry but also reinforces the importance of protecting the oceans as strategic allies in the fight against climate change.
