08b area2 Production of Platform Chemicals by Bioconversion of Plastic Waste

The bulk of post-consumer plastics ends up in landfills or in the environment. In principle, most discarded plastics can be recycled. In practice, the standard approaches generally yield materials that are of lower quality than the initial product, resulting in “downcycling”, or a loss of value. In contrast, we think that a bioconversion process can upcycle plastic waste, yielding value-added biochemicals and other biological products. The mission of Southeastern Biochemicals (SEB) is to produce high quality, competitively priced biochemicals using sustainable biotechnology. SEB believes that the key to operating a profitable biochemical refinery is to have a facility that can process multiple feedstocks and rapidly change its products based on demand and profit margins. In this DOE SBIR Phase I project, inputs to the biochemical refinery will be expanded to include plastic waste. SEB’s partners at Georgia State University (GSU) have developed processes to use plastic waste as a feedstock for a biochemical refinery. The GSU processes depolymerize plastics into “bite-size pieces” that microorganisms can metabolize into biochemicals. Notably the processes can accommodate food-contaminated plastics, which are presently discarded by materials recovery facilities and are not recycled. Initially, the inputs will be PET and polypropylene and the major products will be oleochemicals including palmitic acid, oleic acid and stearic acid, commercially valuable fatty acids which are used for making detergents, lubricants and other products, a multibillion-dollar market. Residual biomass is also saleable as fertilizer; in sum, nearly 100 percent of the waste input will be sold. Overall, the project takes advantage of the low cost of plastic waste acquisition and the high value of biochemicals to help maximize profitability. The experimental objectives of the work are to optimize cell growth and fatty acid production by manipulating nutrient availability and by changing environmental parameters (pH, osmolarity, oxygen availability). Production will be scaled up to 50-liters. Concurrent with the laboratory research, issues surrounding the biochemical refinery logistics and operation will be addressed. Both the science and the engineering aspects of the project are high risk, advance their respective fields and are potentially disruptive to the oleochemical industry in ways that benefit the economy and the environment. The team brings together expertise in science, engineering and business that will effectively determine the feasibility of the project. Developing a plastic-based feedstock for a biochemical refinery will positively impact the issue of global plastic pollution by redirecting it to a profitable use. This will benefit both landfill space and help keep plastics out of the environment. Further, the proposed solution addresses “dirty” plastics, such as those contaminated with food or dirt, which are currently unrecyclable. A successful demonstration of SEB’s biorefinery design will encourage others to pursue similar approaches, leading to market sector growth and greater waste plastic recovery. Funding of this Phase I project will position SEB to be eligible for matching funds from the Georgia Research Alliance, a state-funded technology incubator, helping SEB accelerate project development.