Green tyres: UniTrento leads European project

Playgrounds and sports fields are often made with a rubber floor surface which is obtained from recycled tyres. In recent years, however, it has been discovered that used tyres, especially at high temperatures, release into the atmosphere polycyclic aromatic hydrocarbons (PAHs), which are dangerous substances. Exposure to high levels of these substances can pose risks to human health and the environment.
For this reason, the European Union has introduced significant restrictions on the use of these materials for the production of synthetic grass mats or rubber floors in public gardens. IPAs, however, are also released into the atmosphere by new tyres during their life cycle. In this regard, the new Euro7 regulation, which recently entered into force, provides that vehicles will also be regulated in terms of the particles emitted by their usable materials and components: tyres, but also components, such as the gearbox, clutch and brakes. Looking ahead, as electric vehicles will become more common, this type of emissions will become prevalent.
What can we do to limit the environmental impact of these products? This is the problem that the research group led by Stefano Gialanella, professor of Materials Science and Technology at the Department of Industrial Engineering of the University of Trento, will try to solve with Andrea Dorigato, Luca Fambri and Giulia Fredi.
The research project is called "NORUBTREET_4_LIFE" and has recently obtained European funding amounting to 898,717 euros. These funds are part of the Life Horizon Europe programme, which supports interventions and initiatives focused on the environment, quality of life and the circular economy.
The aim is to develop a recycling process for used tyres to create new compounds for new, non-polluting tyres, which also satisfy the emission requirements including in terms of toxicological and environmental impact.
The study is coordinated by the University of Trento and brings together four European partners: the Royal Swedish Institute of Technology (Sweden), the University of Groningen (Netherlands), the University of Milan and Marangoni Spa.
The research starts from a collaboration with the University of Groningen, where a process for recycling tyres has already been developed, but on a small scale.
There are two main research lines: measuring the fumes emitted by these recycled products generated in the Netherlands, and verifying that they do not contain toxic substances such as polycyclic aromatic hydrocarbons.
"Should they contain toxic substances – explains Stefano Gialanella – we would have to modify the production process and create materials with other mixes that would be tested in the laboratory. We will compare the emissions of average European tyres that are already on the market with those of the materials we are going to produce. We expect positive results in terms of both environmental and economic impact."
Based on the estimates reported in the study, greenhouse gas emissions are reduced by 30 percent in the production cycle. The purchasing cost should be reduced by 25 percent.
The project will first produce tyres for heavy-duty vehicles (trucks, excavators, construction vehicles).
But the goal is wider. "We focus on tyres – he explains – and on what to do with them now that they have been banned. However, the information we will obtain will be useful to know if the air we breathe on the playground or during a tennis game contains harmful substances."