UPLIFT has developed and scaled-up 2-3 innovative bio-upcycling processes by integrating fossil-based plastic monomers (obtained by chemo-enzymatic depolymerization) with bio-based (fermented) building blocks, in order to obtain more renewable polymers. We call this concept a “Plastic Biorefinery”, since it can combine the valorization of organic waste streams (to obtain bio-based building blocks) with the valorization fossil-derived monomers from plastic waste. This resulted in the production of ≈20Kg of bioplastics that has improved properties for food and drink packaging and are easier to recycle.
In this way, UPLIFT will contribute to 1) increase recycling rates, and 2) the increase of bioplastics and renewable materials, thus reducing our dependency on fossil resources. The chemo-enzymatic depolymerisation of food and drink packaging has the advantage that it can be applied without the need of previous sorting of the mixed plastic waste as is the case in conventional mechanical recycling; moreover, eventual contamination from food residues which hinders their mechanical recycling does not represent a problem in UPLIFT (but rather a source for cell growth). Besides, cascade enzymatic depolymerisation reduces downstream processing complexity and cost, allowing for a stepwise release of specific monomers, instead of creating a complex soup of multiple monomers.
The UPLIFT approach has also the potential to decrease the production cost of expensive bioplastics that are currently not competitive on the market. In fact, UPLIFT preliminary results suggest that the plastic biorefinery, if coupled with increasing recycling rates, has a beneficial effect on the economic viability of upcycled plastics. Bioupcycling PET into PET or PTT would for instance allow to obtain recycled rPEF and rPTT at lower cost. This should provide effective motivation and driving force to increase recycling rates and suggests that the plastic biorefinery concept could play an important role in the transition to a more bio-based and circular plastics sector. In other words, increasing the recycling rates of eco-polymers obtained through the UPLIFT biorefinery approach can actually decrease production costs and thus convince producers and consumers to become part of a much-needed joint recycling effort. This is the opposite of what we observe in the fossil-based plastics, where recycled materials cost more than those obtained from virgin resources.
Moreover, UPLIFT has developed a one-pot enzyme production and plastic hydrolysis without the need for enzyme purification (simply using the enzyme-rich supernatant). Besides, UPLIFT has also developed novel eco-polymers and bio-based aromatic polyesters, that allow for easier recycling. Last but not least, UPLIFT also developed a Biotechnological approach that is able to efficiently recycle multilayer plastic packaging, such as drinking cartons.
Designing for recyclability: Eco-design of renewable and easy-recyclable ecopolymers will pave the way to a more sustainable plastic system, making packaging an available feedstock for the circular economy, also thanks to a biorefinery approach. By keeping plastic waste in the loop, UPLIFT will reduce plastic waste generation and greenhouse gas emissions associated with its production. Finally, UPLIFT has developed a proof of concept for a unique tandem chemo-enzymatic process that allows to bioupcycle real mixed plastic waste (rich in non-recyclable polyolefins) into ecopolymers and bioplastics. Overall, the project will support the transition to more efficient and circular plastic sector, complementing the current mechanical and chemical recycling.
