The Building Blocks of Plastics Circularity

Advanced recycling can inform packaging design and support a circular economy for plastics.

By Dr. Jack Dever, Chief Technology Officer at AVN Corporation

In the packaging industry, a circular model requires a full life cycle view of material choices, designs, and structures. Image courtesy of AVN Corporation.

Sustainable development is at the top of the agenda for forward-thinking companies. Driven by societal expectations and government mandates, sustainability continues to change the way goods are produced, consumed, and disposed of around the world. Initiatives like the United Nations Sustainable Development Goals (SDGs) seek to provide a framework for the pursuit of a healthier and safer world by identifying goals and actions that protect people and the planet with sustainable processes. Companies are committing to ambitious sustainability goals and transparent reporting practices that align with the SDGs as well as contributing to programs like the Alliance to End Plastic Waste, which raised $375 million in 2023 alone.[1]

Plastic circularity represents an important part of many companies’ efforts to increase their sustainable practices. From reducing waste to driving innovation, building a circular economy has numerous benefits related to sustainability. In the packaging industry, a circular model requires a full life cycle view of material choices, designs, and structures. The plastics industry is worth more than $370 billion in the U.S. and plays an important role in many other industries including food, pharmaceuticals, and automotive manufacturing.[2] Recyclers, material suppliers and manufacturers are developing ways to recover and reuse plastic packaging in high value applications, transforming post-consumer recycled (PCR) plastic into an essential commodity for packaging manufacturers.

Supporting the shift towards a circular economy begins with designing packaging for recyclability, which involves a thorough understanding of the science behind recycling technology. The type and structure of plastic impacts how a package is produced and how it can be recycled. Companies looking to become more sustainable must understand the recycling options and how materials can be repurposed to impact the recycled material supply chain. To achieve circularity, bringing plastics down to their most basic building blocks during the recycling process creates versatile, high quality PCR materials that can be reutilized at maximum value.

From a chemical perspective, this involves designing facilities and processes that can sort different types of plastics and remove impurities to create high quality recyclate. There are still many technical challenges to building the recycling systems needed to accomplish a circular economy for plastics, but there are also many opportunities to make plastics production and packaging manufacturing more sustainable with the right support and investment.

Recycling Infrastructure

The collection of post-consumer plastics is the first obstacle to circularity. There are currently many disparate programs that capture plastic waste, from curbside pickup recycling to store drop-off programs, and confusion persists about which types of plastic are recyclable and where they are accepted. Access to recycling facilities varies depending on local laws and policies, but recycling initiatives have historically received minimal investment.

As part of President Biden’s Investing in America agenda, the U.S. Environmental Protection Agency (EPA) contributed over $100 million to recycling and waste management projects across the country in 2023, marking the largest EPA investment in recycling in over 30 years.[3] In a report from The Recycling Partnership, however, it is estimated that an investment of $17 billion will be needed to provide recycling access to everyone in the U.S.[4] More initiatives are needed to expand recycling infrastructure and increase the recycling rate for plastics.

After collection, sortation practices must be determined based on the type of plastic and how it will be reused. When plastics are mixed for recycling, the resulting feedstock is of lower purity and quality and can only be used in limited applications. The practice of downcycling mixed plastics is useful, but ultimately does not support true circularity. Breaking plastics down to high quality monomeric feedstock through advanced recycling allows recyclers to create recycled products that can reenter the market in similar applications to their original use, preventing them from becoming waste and entering landfills.

Technological Challenges

Decomposing plastics to basic chemical building blocks reduces the use of fossil fuels in the supply chain by limiting the use of virgin materials.[5] Multiple advanced recycling technologies exist, including methanolysis, hydrolysis and pyrolysis, and the ideal method depends on the materials being recycled and their intended future use. Although these options are already available, the real technological challenge lies in separation and the removal of impurities.

For example, PET beverage bottles are readily recycled. They are made from food grade materials and are easy to clean and prepare for recycling. Other types of packaging, however, are not so simple to prepare for recycling. Polyester cloth can include cotton or other materials in the thread and dyes. Multilayer food packaging may include layers of different types of plastics and additives. Impurities from different materials or different types of plastics can significantly impact the quality of the monomers produced after recycling. These considerations impact the design of recycling processes, and they can also be used to inform product design for companies seeking to improve the recyclability of their packaging.

Process Intensification

In addition to separation techniques, research is being conducted to improve and expand advanced recycling technology. Many methods rely on thermal energy to break down plastics, and more innovation is needed to develop alternatives that do not rely on combusting fossil fuels to generate the needed heat. This involves process intensification, which aims to streamline chemical processes to reduce energy needs and increase productivity and sustainability.

Some process intensification research is being supported by public and private partnerships in research institutes created by the program Manufacturing USA. The Rapid Advancement in Process Intensification Deployment (RAPID) Institute supports technologies that combine multiple steps into more efficient processes. Advances are being made to electrify processes and discover new methods, such as heat pump-assisted distillation[6] and non-traditional energy sources like the use of microwaves[7] to break down plastics.

Achieving Circularity

According to the Alliance to End Plastic Waste, about half of all plastic waste comes from packaging.[8] By learning about and supporting recycling innovation, companies can gain insight into how to design packaging to support a circular economic model and bring about industry-wide systemic change. Novel technologies with sustainable processes can direct material selection for packages designed to be recycled and repurposed.

Although significant progress has been achieved, plastics circularity still has a long way to go. Waste collection infrastructure, separation techniques, and advanced recycling methods must be further developed and scaled with capital from players across the value chain. The investments needed are large, but the payoff will be worth it. Closed Loop Partners estimates that the circular economy will more than double in the next ten years, adding more than $100 billion to the global economy.[9] In the long term, circular plastics can lower the need for ethane crackers by reducing the use of virgin plastic. Advanced recycling is the foundation of circularity, allowing companies to reuse post-consumer packaging as raw materials for new products in sustainable, circular processes.

About the Author

Dr. Dever oversees lab, pilot plant and manufacturing technology at AVN Corp., an innovation partner in chemical process research, development, engineering and commercialization. Learn more at www.avncorp.com.

[1] Alliance to End Plastic Waste, Advancing Circularity: Solutions for Change, 2023. https://endplasticwaste.org/en/our-stories/-/media/9C3B24612019470B991A9DCB405F357A.ashx.

[2] American Chemistry Council, U.S. Plastics by the Numbers, 2023. https://www.americanchemistry.com/better-policy-regulation/plastics/resources/us-plastics-by-the-numbers.

[3] EPA, Biden-Harris Administration Invests More than $100 Million in Recycling Infrastructure Projects Through Investing in America Agenda, https://www.epa.gov/newsreleases/biden-harris-administration-invests-more-100-million-recycling-infrastructure-projects.

[4] The Recycling Partnership, Paying it Forward: How Investment in Recycling Will Pay Dividends, 2021. https://recyclingpartnership.org/wp-content/uploads/dlm_uploads/2021/05/Paying-It-Forward-5.18.21-final.pdf.

[5] America’s Plastic Makers, Report: Advanced Recycling of Plastics Reduces Greenhouse Gas Emissions, Fossil Energy Use, 2022. https://plasticmakers.org/wp-content/uploads/2022/10/ACC-Key-Findings-10-2022-vFinal.pdf.

[6] Applied Thermal Engineering, Optimization of energy-saving distillation system of absorption heat pump based on intermediate heat exchange.https://www.sciencedirect.com/science/article/abs/pii/S1359431122006652. https://www.sciencedirect.com/science/article/abs/pii/S1359431122006652

[7] Cleaner Engineering and Technology, Chemical recycling of plastics assisted by microwave multi-frequency heating, 2021. https://www.sciencedirect.com/science/article/pii/S2666790821002573.

[8] Alliance to End Plastic Waste, The Plastic Waste Management Framework, 2023. https://endplasticwaste.org/en/our-stories/plastic-waste-management-framework.

[9] Closed Loop Partners, 2023 Impact Report, 2023. https://www.closedlooppartners.com/wp-content/uploads/2024/06/Closed-Loop-Partners-Impact-Report-3.pdf.