Like the lingering bit of advice from 1967’s “The Graduate,” plastics as a field of opportunity is being reimagined for the blockchain age. But this time, it’s for plastics recycling.

Blockchains are proving extremely useful for tracking materials across all sorts of supply chains and creating transparent and immutable audit trails. Meanwhile, governments around the world are issuing legislation requiring retailers and plastics producers to show they are meeting minimum levels of recycling, requirements that are likely to intensify going forward.

That’s where a handful of blockchain startups see opportunity, by connecting major refining companies with new types of plastics recycling in a bid to reinvent current supply chains. Blockchain’s appeal here: measuring action and demonstrating it to the public.

Currently, only rigid plastics that go into things like bottles are mechanically recycled into lower-grade plastics, a process that can be repeated twice at the most. But a combination of clever industrial technologies is set to make plastics recycling more sophisticated over the next few years, returning the chemically altered raw materials back into the manufacturing process.

This means reducing plastic to the crude sludge from whence it came and then refining it again into any order of new products, creating a completely circular economy for a waste product that has become a scourge to the planet (as much as 12 million tons of waste plastic enters the oceans each year).

The prospect of chemically recycled plastic entering global supply chains is the next step for large oil and gas refining companies, said Juan Miguel Perez, CEO of Finboot, which uses enterprise blockchains to help firms measure and reduce their carbon footprints.

Finboot is working with Repsol, the Spanish energy giant committed to achieving net zero emissions by 2050. (Repsol acquired an 8 percent stake in Finboot in July of last year.)

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Repsol, which creates polypropylene used in plastic bottles, is now looking to take the lead in plastics recycling, showing how this could demonstrably transform downstream supply chains.

“It’s a hard goal, but eventually you could show how consumer plastics from waste collection companies can be added into your supply chain as raw materials,” Miguel Pérez said. “It’s the next step in the process of tracing assets and linking supply chains.”

Repsol was not ready to comment on its chemical plastics recycling at this time.

Mining the wasteland

U.K.-based startup Circulor is also looking at tracing recycled plastic across supply chains, going beyond the work it’s doing with conflict minerals like cobalt.

“I’m very excited about plastic waste,” said Circulor CEO Doug Johnson-Poensgen. “In many European countries, governments are proposing taxes on retailers who sell plastic which doesn’t contain a minimum of 30 percent recycled. The obvious thing that’s required is a way to prove it, which is what blockchains can do.”

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The same issue is faced at an oil refinery, he said. “The challenge for the oil majors like Total and BP is that if you are producing all these plastic materials, how much of it is recycled? This is why traceability is an important part of that.”

The chemical recycling of plastic is the future, said Johnson-Poensgen, and the proper infrastructure to do this is gradually being put in place, adding that Circulor is “scoping out” a project with U.K.-based Recycling Technologies, which manufactures the equipment to chemically recycle plastic.

Recycling Technologies, which this month received backing from Neste, the world’s leading provider of renewable diesel and jet fuel, creates seed stock for new plastic production. This also improves on mechanical means by incorporating so-called soft plastics, which generally end up in landfills or simply bleed into the environment, said Recycling Technologies marketing manager Lisa Zafferani.

Her company uses a system of thermal cracking, turning waste plastic into a gas which can then be distilled into an oil and refined by a petrochemical firm, in the same way crude oil from the ground is refined.