A novel ocean capture technique has emerged that converts carbon dioxide from seawater into plastics, potentially addressing the urgent issue of ocean acidification and its effects on marine ecosystems. The method, known as Direct Ocean Capture (DOC), involves extracting dissolved CO2 through electrochemical processes. While various companies are exploring this technology, it has yet to be implemented on a large scale, with financial feasibility remaining a concern. Researchers from the Chinese Academy of Sciences and the University of Electronic Science and Technology of China have developed an innovative process that not only captures CO2 but also transforms it into biodegradable plastic building blocks at a significantly lower cost.
Their approach demonstrates an efficiency of 70% while utilizing minimal energy—approximately 3 kWh for each kilogram of CO2 captured. The process begins by using electricity to acidify seawater, which allows the dissolved CO2 to be transformed into a pure gas. Once collected, the water is restored to its original state before being returned to the ocean. The next phase involves introducing the captured CO2 gas into a reactor with a bismuth-based catalyst that produces formic acid, a key component used by engineered marine bacteria, specifically Vibrio natriegens.
These modified microbes metabolize the formic acid and generate succinic acid, which is vital for creating biodegradable plastics such as polybutylene succinate (PBS). The researchers believe there is potential for further optimization and integration of this process into existing industrial frameworks, with prospects for producing a range of chemicals for fuels, pharmaceuticals, and food products as well. While the outlook is promising, the path to commercialization may face challenges, especially as competitors like Brineworks aim for similar cost reductions. The next few years are expected to be crucial in the development of this cutting-edge decarbonization technology.