The incredible new tech that can recycle all plastics, forever

“Advanced recycling” promises to convert dirty, mixed waste plastic into brand new plastic time and time again. It is a major step towards creating a circular economy and fighting climate change…..

A suite of “advanced recycling” technologies is gradually coming on stream, promising to take used plastic of any type and convert it into something extremely useful: plastic.

The goal is to create a circular economy for this material where there is no longer any need to make virgin plastic from crude oil, just endlessly recycle what we already have. Plastic, rightly demonised as a scourge of the modern world, could be fantastic again.

There is plenty of it to work with. Since the 1950s, we have produced over 10 billion tonnes of the stuff. More than 8 billion tonnes of that has ended up as waste. Much of it is still hanging around in landfill and the environment, and the deluge keeps coming.

The world currently generates around 350 million tonnes of plastic waste each year, according to Suhas Dixit, CEO of plastics recycler APChemi in Mumbai, India.

In 2017, a team led by Roland Geyer at the University of California, Santa Barbara, analysed the fate of all plastic ever made. That work still gives us the best overall picture of what happens to the stuff — and it isn’t pretty (see graphic, below).

About 55 per cent was sent straight to landfill or discarded, 8 per cent has been incinerated and only 6 per cent recycled — and, of that, most was then subsequently discarded to landfill.

It goes without saying that all this is a horror for the environment. Plastic that is burned or that decomposes in landfill releases vast amounts of greenhouse gases into the atmosphere. And somewhere between 10 and 15 million tonnes of plastic finds its way into the oceans each year, creating informal rubbish dumps like the Great Pacific Garbage Patch.

This profligacy contributes hugely to the three great planetary crises of our time — climate change, biodiversity loss and, of course, waste and pollution. There is also growing concern about the impact of plastic on human health.

We persist in using the stuff because it is so useful. This is down to the fact that it comes in a diverse range of chemical forms that can do almost any job. What unites them is that they all start with monomers: small molecules with two reactive ends. Under the right conditions they join up like carriages in a train to create long, repeating strings called polymers.

Start with a monomer called ethylene, for instance, and you get polyethylene. Strong, transparent and flexible, it is the world’s most abundant plastic, mostly used to make drinks bottles. Other plastics are “copolymers” consisting of two or more types of monomer. Finished plastics also contain additives — lubricants, flame retardants, pigments and more…..