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Recycling plastics

| By Dorothy Lozowski

Separating recyclables from our trash has become commonplace for many of us. What can be recycled and how it is collected, however, varies quite a bit by location. My town, for example, accepts plastics #1 (polyethylene terephthalate; PET), #2 (high-density polyethylene; HDPE) and #5 (polypropylene; PP). Other locations accept plastics #1–7, which includes low-density polyethylene (LDPE), polystyrene and others. Some towns collect plastics together with metals and glass, and others do not. This variation in collection protocols in the U.S. can be confusing to consumers and is one of the big hurdles to advancing plastic recycling.

A recent report [1] from the National Academies of Sciences, Engineering and Medicine ( finds that private- and public-sector recycling efforts are not well coordinated and says that “action from the public sector at the federal, state and local levels is needed to improve the plastics waste-management system in the U.S.” The report states that recycled plastics are an underutilized resource, and that only about 10% of plastics waste is recycled in the U.S.


Using recycled plastics

The National Academies report summarizes a study that was sponsored by the U.S. Dept. of Transportation and the U.S. Environmental Protection Agency to look at the potential use of recycled plastics in infrastructure. Potential infrastructure applications include asphalt pavement mixes, drainage pipes, railroad ties, bicycle paths, composite utility poles and highway sound barriers. Of these, only drainage pipes shows significant demand at present, according to the report, and more knowledge about a number of factors, including long-term performance, is needed for further adoption. The four plastics with properties that are most suited for infrastructure applications — PET, HDPE, PP and LDPE — are also in demand for applications such as carpeting, clothing and bottles. The report says that more recycled plastics are needed to meet the demand.


Processing technologies

As the demand for recycled plastics increases, companies are investing in processing technologies and facilities. Nova Chemicals Corp. (, for example, recently announced that it is developing its first mechanical recycling facility to convert post-consumer plastic films to recycled polyethylene (rPE) at commercial scale as early as 2025. The facility, to be located in Connersville, Ind., is expected to deliver over 100 million lb of rPE by 2026.

Nova has also announced that it, together with Plastic Energy, will study the feasibility of developing a pyrolysis-driven advanced recycling facility for polyethylene in Ontario. If built, the facility is expected to be the largest of its type in Canada. Advanced, or chemical recycling, can produce plastics with the same properties as virgin material.

Late last year, ExxonMobil Corp. ( announced the successful startup of its advanced recycling facility in Baytown, Tex. The facility is said to be able to process 80 million lb/yr of plastic waste.

More news on recycling facilities and technologies can be found in “The Latest” section on our website ( and by subscribing to our free “Sustainability Direct” E-newsletter.■

Dorothy Lozowski, Editorial Director

1. National Academies of Sciences, Engineering and Medicine, Recycled Plastics in Infrastructure: Current Practices, Understanding, and Opportunities, Washington, D.C., The National Academies Press, 2023.