Exploring the Economic and Environmental Benefits of Solvent-Based Recycling Processes of Multi-Layer Plastic Films

Multi-layer plastic films are fascinating materials that are widely used for food packaging; these films are strategically designed to harness specific protection properties of different polymers (e.g., oxygen, moisture, and temperature barriers). These properties are essential to facilitate food storage and distribution in supply chains, as they enable long shelf lives, reduce refrigeration use, reduce food waste, and facilitate food accessibility. Unfortunately, multi-layer plastic films cannot be mechanically recycled using traditional approaches. As a result, large amounts of multi-layer films typically end up in landfills or are combusted. Solvent-based approaches have emerged as a promising alternative to separate and recycle the constituent polymers of multi-layer films. This process uses a series of solvent washes to dissolve and precipitate polymers in a targeted manner. Quantifying the economic and environmental benefits of solvent-based recycling processes is essential for their deployment and for enabling more circular economies.

This work presents a computational framework to conduct a detailed economic and environmental analysis of solvent-based recycling processes. The proposed framework integrates process simulation models, life cycle assessment methods, molecular simulations, and experimental data. Our analysis highlights critical components of the processes (specific unit operations and solvents) and of the multi-layer films (specific polymer layers) that have the highest economic and environmental impacts. I will discuss how our findings are currently guiding advances in process, product, and supply chain designs that are more sustainable.