Among chemical recycling technologies, pyrolysis is one of the most promising. In pyrolysis, plastics are heated to high temperatures without oxygen, causing them to break down into gases and liquids. The TREASoURcE project aims to utilize this technology through catalytic pyrolysis to produce high-value aromatic compounds such as benzene, toluene and xylene (BTX). These compounds serve as essential materials in the chemical industry, with applications in plastics production, synthetic fibers, pharmaceuticals, paints and more.
To accomplish this objective, a detailed process scheme has been developed, as illustrated in Figure 1.
Extensive laboratory-scale testing has shown that plastic waste can be efficiently converted into BTX components. Using an optimized catalyst in a single-fixed bed system, the project team produced BTX equal to 22% of the weight of the plastic fed into the reactor. In a dual-bed system, the BTX yields increased to 40% at 550 °C. Further tests using a single-bed bench-scale fluidized system produced about 37% of the plastic as condensable liquid products, and nearly 80% of that liquid by weight was BTX. These results highlight the strong potential of the catalytic pyrolysis process to convert difficult-to-recycle waste into valuable raw materials, contributing to sustainable resource recovery and a circular economy.
Scaling Up the Process
The next phase of the project involves scaling up the process to handle the best plastic waste from the previous small scale experimental work, including industrial, household, and agricultural sectors in the scope of the project.
As illustrated in Figure 2, two experimental configurations will be used to scale up the pyrolysis process from bench scale, at Technology Readiness Level (TRL) 3–4, to pilot scale, with TRL 6. The process development unit (PDU), which operates at a feed rate of 2 kg/h, corresponds to Technology Readiness Level (TRL) 4–5, meaning the technology has been validated in a laboratory or a relevant environment. The pilot unit, designed for a capacity of 20 kg/h, corresponds to TRL 6, indicating the technology has been demonstrated in a relevant industrial environment.
Both systems are equipped with separate catalyst regenerators to ensure stable, continuous operation. After respective pyrolysis test runs (thermal and catalytic), the vapor products will be condensed in fractional condensers to separate BTX rich product. The resulting liquid products from the catalytic pyrolysis process will subsequently undergo distillation for purification, followed by thorough analysis to verify product quality and ensure that it meets the standards required for industrial applications.
Driving Innovation for Sustainable Plastic Management
By combining advanced catalytic technologies with scalable reactor designs, the TREASoURcE project aims to pave the way for a circular economy for plastics. Turning plastic rejects waste from mechanical recycling into high-value BTX aromatics not only reduces environmental pollution but also creates a sustainable source of raw materials for the chemical industry. Implementing this strategy can significantly increase recycling rates of plastic waste currently incinerated, while reducing dependence on fossil resources. This approach supports the EU’s circular economy and sustainability targets for 2025 and beyond, including waste reduction, enhanced resource efficiency, and closed-loop material cycles. Advancing these recycling technologies is essential for achieving a sustainable and circular plastic economy in alignment with current environmental objectives.
23.9.2025 | Muhammad Hassam Khan, Farah Siddiq & Sirous-Rezaei Pouya (VTT, Technical Research Centre of Finland)
For more information, contact: farah.siddiq@vtt.fi