FMSG:ECO: CAS:From Carbon Dioxide to Future Bioplastic Manufacturing for Environmental Sustainability

Replacing petroleum-based products with inexpensive, renewable, natural materials is essential for sustainable development and will significantly impact the polymer industry and the environment. Petroleum-based plastic materials have exceeded most other man-made materials and are present as must-have materials in modern life. It is estimated that the total amount of plastic resins and fibers manufactured from 1950 through 2015 is 7800 million tons, half of which was produced in the past decades. Biodegradable plastics have been long sought-after as alternatives to petrochemical plastics to promote environmental sustainability. Even though bioplastics provide substantive environmental benefits, the current manufacturing cost is relatively high. In this Future Manufacturing Seed Grant (FMSG) project, the project team will develop a new manufacturing process to convert CO2 to bioplastics (polyhydroxyalkanoates, PHA) and design bioplastics composite to enable future manufacturing. CO2 will be converted to edible microbial nutrients via a process known as electrocatalysis, and the nutrients will further be used by bacteria to produce PHA. Microbe-derived PHA will be used to make bioplastic composites. The project will engage undergraduate and graduate students, utilize a university training center to educate broad audiences, and build global impacts in Africa.The project aims to develop a new manufacturing process to convert CO2 to bioplastics (polyhydroxyalkanoates, PHA) and design bioplastics composite for broader applications. Traditional industrial fermentation has an inherent carbon efficiency limitation using sugar-based feedstock. The limited reducing equivalent supply during carbon conversion inevitably leads to carbon emission and lowers carbon efficiency in heterotrophic microorganisms. The proposed research will create a cost-effective manufacturing of industrial quality bioplastics. The research will establish an electrochemistry-bioconversion hybrid system for efficient and cost-effective PHA production. Electrolysis-supported catalytic pathways for CO2 conversion to acetate, ethanol, and propionate will be created and optimized. The team will integrate a two-step tandem process with a state-of-the-art Cu catalyst to achieve a highly selective acetate/ethanol production at high reaction rates. Pseudomonas strains will be engineered to convert C2 and C3 intermediates to PHA with a high efficiency. Techno-economic analysis (TEA) and life cycle analysis (LCA) will be measured to evaluate the economic and environmental impacts of new created PHA composites. The fundamental knowledge gained from this process will bring transformative changes to the current manufacturing and climate mitigation.This project is jointly funded by the Division of Molecular and Cellular Biosciences in the Directorate for Biological Sciences, the Division of Chemical, Bioengineering, Environmental, and Transport Systems in the Directorate for Engineering, and the Division of Chemistry in the Directorate of Mathematical and Physical Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.