Researchers report in Nature Catalysis a prototype system that captures dissolved CO2 from seawater and converts it into biochemical feedstock for bioplastics. The artificial ocean carbon recycling system ran for 536 hours with a reported 70% capture efficiency and an estimated cost of $230 per ton of CO2. Presented as the first end-to-end demonstration from oceanic CO2 to bioplastic precursor, the work could reduce fossil feedstock use, though scale-up, energy sourcing and ecological impacts require further study.
Ocean CO2 to Bioplastic Feedstock — First Demonstration of Seawater Carbon Capture and Conversion
Researchers report in Nature Catalysis a prototype system that captures dissolved CO2 from seawater and converts it into biochemical feedstock for bioplastics. The artificial ocean carbon recycling system ran for 536 hours with a reported 70% capture efficiency and an estimated cost of $230 per ton of CO2. Presented as the first end-to-end demonstration from oceanic CO2 to bioplastic precursor, the work could reduce fossil feedstock use, though scale-up, energy sourcing and ecological impacts require further study.
07:45 AM, 11/16/2025Science
Researchers convert dissolved ocean CO2 into feedstock for sustainable plastics
A multinational team of scientists reports the first demonstration of a process that captures dissolved carbon dioxide from seawater and converts it into biochemical precursors for bioplastics. The research, published in Nature Catalysis, was led by the Shenzhen Institutes of Advanced Technology of the Chinese Academy of Sciences with collaborators from the University of Electronic Science and Technology of China.
What they built
The researchers developed an artificial ocean carbon recycling system that uses a decoupled electro-biocatalytic hybrid process to extract dissolved inorganic carbon (DIC) from seawater and convert it into value-added chemicals. The prototype is driven by renewable electricity in concept and is designed to turn oceanic carbon sinks into useful feedstocks rather than releasing that carbon to the atmosphere.
Key results
The system ran continuously for up to 536 hours and achieved a reported 70% capture efficiency for dissolved carbon. The team estimated the capture cost at roughly $230 per ton of CO2. These metrics represent an early proof of concept for moving from oceanic CO2 all the way to a usable bioplastic monomer.
"Renewable electricity-driven capture and conversion of oceanic dissolved inorganic carbon into value-added chemicals offers a sustainable route towards negative carbon emissions and a circular carbon economy," wrote the authors.
Why it matters
Most conventional plastics are produced from fossil-derived feedstocks. By providing an alternative, low-carbon feedstock pathway, the method could help manufacturers reduce reliance on fossil fuels, lower greenhouse gas emissions and address plastic pollution by promoting more sustainable production chains.
Caveats and next steps
While promising, this remains a prototype demonstration. The researchers and outside experts note that further work is needed to evaluate scalability, full lifecycle emissions, energy sourcing (the approach assumes renewable electricity), economic competitiveness at industrial scale, and potential ecological impacts of large-scale seawater processing. Additional engineering, environmental assessment and cost reductions would be required before commercial deployment.
"This is the first demonstration that's going from ocean carbon dioxide all the way to a usable feedstock for bioplastic," said Dr. Chengxiang Xiang of Caltech's Joint Center for Artificial Photosynthesis. "The primary goal is taking that CO2 and turning it into a bioplastic monomer with promising stability and economics."
The study adds a novel option to the portfolio of carbon capture and utilization approaches, highlighting the ocean carbon pool as a potential resource for sustainable chemistry—while underlining the importance of careful evaluation before scaling up.