Can tires turn green?

Abstract

Tires’ substantial environmental footprint is set to drop as producers increase their use of renewable materials and efficient technologies emerge for chemically recycling them. Currently, most tires are incinerated or landfilled, at a high environmental price. While the sector’s footprint may be shrinking, millions of metric tons of rubber particles get released annually as tires wear down on roads. And independent scientists say this pollution is a cause for concern. The tire industry says it is trying to understand the impacts of these particles. Until issues around them are addressed, however, the sustainable tire will remain out of reach. Rubber crumbs rain down onto more than 150 electric heating plates, raising their temperature to over 600 °C within seconds. In an atmosphere depleted of oxygen, the crumbs rapidly transform into a gas, which is cooled into a synthetic oil and a solid that is mostly carbon black. This process is