Engineers Develop Scalable Bacteria-Based Method to Convert Atmospheric CO2 into Polyester
As the threat of climate change looms larger, scientists worldwide are relentlessly exploring ways to prevent and remove emissions from the atmosphere. In this innovative study, the researchers focused on...
A recent breakthrough by a team of chemical and biomolecular engineers at Korea Advanced Institute of Science and Technology (KAIST) could pave the way for a sustainable solution to mitigate climate change. The team has developed a scalable technique that utilizes bacteria to convert carbon dioxide (CO2) in the air into a type of polyester. The results of their research were published in the Proceedings of the National Academy of Sciences.
As the threat of climate change looms larger, scientists worldwide are relentlessly exploring ways to prevent and remove emissions from the atmosphere. In this innovative study, the researchers focused on the potential of Cupriavidus necator, a bacterial species, to extract CO2 from the air and transform it into a polyester variant.
Previous studies demonstrated that C. necator can absorb CO2 and generate specific types of biodegradable plastics. However, the process was restricted to small batches due to the requirement of electricity to initiate the process, which led to toxic byproducts that killed the bacteria, preventing scalability.
The researchers at KAIST tackled this issue by incorporating a synthetic membrane at the beginning of the process to shield the bacteria from the toxic byproducts. This approach created a two-sided process wherein one side carried out chemical reactions to prepare CO2 for fermentation, while the other side contained the necessary ingredients. The membrane enabled these ingredients to gradually flow towards the bacteria, which then produced poly-3-hydroxybutyrate (PHB) fragments.
Over a period of 18 days, the research team continuously replaced bacteria loaded with PHB with fresh, empty samples. The process yielded 11.5 mg of PHB per hour, proving to be successful as planned. Although electricity is still needed, the process is substantially more efficient than other methods, thus reducing the overall cost of converting CO2 into the polyester.
Moreover, the researchers emphasized the ease of scaling up this process, making it a promising avenue for future large-scale applications in combating climate change.
Jinkyu Lim et al, Biohybrid CO 2 electrolysis for the direct synthesis of polyesters from CO 2, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2221438120