Only 9 percent of plastic material in the U.S. gets recovered and put into new products. But several companies are developing ways to chemically break down plastic to its basic building blocks, called monomers.
If they get it right, the environmental implications could be seismic, making it possible for all plastics to be used and reused in an infinitely recyclable loop.
“The advantage with chemical recycling is you end up with a pure liquid monomer, which can be put directly back into the production process,” Andreas Anker, a spokesman for LyondellBasell Industries NV, tells Bloomberg Environment.
LyondellBasell, one of the largest producers of plastic in the world, recently announced a joint venture aimed at developing chemical recycling at an industrial scale.
While chemical recycling of plastics is still at least several years out, Anker says the technology behind the process already exists and is increasingly viewed as the best way to close the loop on plastic supply chains.
“Here in Europe, the issue of plastic recycling has become very important, very quickly,” said Anker, who lives in Germany. “You can see the demand coming from governments, as well as large brand owners and from society in general.”
Since plastic doesn’t biodegrade, developing new ways to break it down has been a goal of companies and recycling advocates for decades. Such a technology would dramatically cut the need for new plastic made largely from petroleum and vastly improve the life cycle of plastics.
Typically, most single-use plastic—known as polyethylene terephthalate or PET—is not recycled. But plastic that is recycled undergoes a mechanical process that involves shredding it down into small pieces, washing it, and then remolding it into new products.
“This works well, but to recycle PET to make new food and drink packaging—so-called food-grade PET—you can only use existing food-grade plastic,” said Maria Luisa Polli, technical director of Coca-Cola Central and Eastern Europe.
In a company publication, Polli said that only 20 percent of all PET is currently recycled, creating a limited supply of good quality, food-grade PET on the market. But by using a chemical decomposition method, any waste plastic could be used to make food-grade PET.
“Not just used plastic bottles, but also waste recovered from oceans and plastic from other sources, like polyester textiles. Ultimately, if all plastic can be recycled, then waste plastic could potentially become a thing of the past,” said Polli.
The process of breaking plastic down, called “depolymerization,” involves using a chemical catalyst to heat the material to around 500 degrees Celsius (932 degrees Fahrenheit). At that point the molecules break, or “crack,” into monomers, such as the hydrocarbons ethylene or propylene.
High energy costs and the need to transport large amounts of plastic waste material to a central facility have traditionally meant that chemical recycling would be expensive compared to the cost of making new plastic. But that calculus is changing quickly.
“Increasingly, these decisions are less about the cost of raw materials, and more about the costs associated with dealing with plastic waste on the back end,” said Franco Cavadini, the chief technical officer with Synesis, an Italian engineering company involved with DEMETO.
DEMETO is a European Union-funded research consortium that has developed a microwave-based process to accelerate the chemical decomposition of plastic, potentially making it much easier to operate on an industrial scale.
“By using microwaves to accelerate a chemical reaction, the depolymerization time goes from three hours to less than 10 minutes,” Cavadini told Bloomberg Environment.
In addition to the recent Chinese ban on imports of recycled products from the West, Cavadini also points to a number of European laws and initiatives that will increase the costs of producing new plastic.
“Our current estimates show our method costing less than monomers produced by petroleum,” Cavadini said. “All the answers we get from technology side confirm the business model.”
Upside for Textiles
The issue of plastic waste isn’t just a problem for food and drinks manufacturers. Plastic is also used in some clothing, and the Council for Textile Recycling estimates that the average U.S. citizen throws away over 80 pounds of clothing each year.
“We need to use resources more efficiently in order to decrease our environmental impact,” said Mattias Bodin, a sustainability business expert for the H&M Group, a Swedish clothing retailer.
Of PET produced each year, the majority goes to make synthetic fibers, such as polyester, according to the PET Resin Association.
In a statement provided to Bloomberg Environment, Bodin said the company has recycled the equivalent of 89 million T-shirts through an in-store drop off program, but chemical recycling would be the biggest game changer for the fashion industry.
“We consider chemical recycling to be of utmost importance for us to be able to achieve our 2030 goal of using only recycled or other sustainably-sourced materials,” he said. “We also know that it makes very good business sense. It’s the only way forward.”