The 2025 lecture series features faculty members leading cutting-edge research in climate science and related solutions, with a focus on understanding the complex processes underlying our climate, developing new technologies for mitigating climate-changing factors, and adapting to new climate conditions.

All lectures are free and open to the public and streamed on Zoom, with recordings available afterward.

Lucas Ellis
Assistant Professor of Chemical Engineering

Tandem approaches in waste plastic recycling and upcycling

Society is facing a series of convergent environmental tragedies, like the collapse in biodiversity, human-caused climate change, the rapid accumulation of waste plastics in waterways and oceans, and more. These challenges will require a diversity of interdisciplinary technologies to be developed and deployed at exceptionally fast rates to market. We have a history of these types of accomplishments, and we can do it again.

In this presentation, I will summarize my recent efforts to create new plastic recycling technologies, since the only free-market approach to combat the plastics problem is to make recycling technologies profitable. The term ‘upcycling’ has gained recent media attention as an attractive means to manage plastic waste, with one key problem: Few technologies exist capable of producing ‘high-value’ products from plastic waste. I will present two plastic recycling approaches. The first combines chemistry and biology capable of depolymerizing mixed plastic waste, like polyethylene terephthalate (PET), polyethylene (PE), and polystyrene (PS), and funneling these compounds into a single product, like a biopolymer or a precursor for nylon product, using an engineered microbe. The second approach uses tandem synergistic chemistry — alkane dehydrogenation and olefin metathesis — to depolymerize polyolefin polymers at temperatures below 200 °C using abundant alkane co-reactants and robust heterogeneous catalysts.