“More than 90% of Polyurethane goes to the incinerator. We are changing that.”
Polyurethane (PU) is everywhere—from mattresses and insulation to refrigerators—yet the vast majority is still burned instead of reused. In this interview, Niels Van Velthoven, founder of the start-up Purtiso, explains how his team is building on more than a decade of KU Leuven research to break PU back down into its original building blocks, enabling true high-percentage recycling. He also reflects on the leap from academia to entrepreneurship, the role of Moonshot Flanders, and why chose Chemelot to pilot Purtiso’s technology.
What problem do you want to solve with Purtiso?
Niels Van Velthoven: “Purtiso works on recycling PU and has technology that can recycle up to 100% of the material and turn it into the building blocks needed to manufacture PU again. There is a huge amount of PU in the world and currently it is not being recycled on a large scale. More than 90% goes to the incinerator. That is a great pity. PU is a relatively expensive substance, which means that recycling it can actually be very valuable. The price of the molecular building blocks to make PU is 2 – 3 times higher than the price of typical plastic monomers. This makes the business case for recycling and reuse stronger than for other plastics. The problem with making PU circular is mainly technological because it is a more complex material.”
It is a more valuable product, yet there is less technology available. Why is that?
Niels Van Velthoven: “Complexity is the biggest barrier. You have two main building blocks, isocyanates and polyols, in different compositions, supplemented with additives, and separating them again is not easy. PU is a thermoset. Melting does not work and pyrolysis releases too much NOx. So you cannot use the standard technologies that work for other plastics. You have to move to more advanced technologies, which is what we are working on with Purtiso. ”
What technology can you use for this?
Niels Van Velthoven: “The best way to recover PU waste is to split the material back down to its building blocks. Either you create a single stream, for example the polyols, or you recover two main streams, isocyanate(-derivatives) and polyols. This requires a lot of process technology, including various solvents and filtrations. The aim is to make your process as cheap as possible. So a good understanding of the chemistry and individual process steps is essential for the commercial development of your overall process.”
How has Purtiso been able to choose a winning technology?
Niels Van Velthoven: “KU Leuven has been researching this problem for over 10 years, which is hugely important for Purtiso. I myself was closely involved in this research as part of Professor Dirk De Vos's team. The research was carried out in collaboration with industry. Companies such as Recticel and Covestro were partners. The knowledge base is enormous, and that is how we arrived at third-generation technology. I became increasingly convinced that we could develop a strong business case.”
So you went from being an academic to an entrepreneur. That's a big step?
Niels Van Velthoven: “I had already founded two other companies that were successful. I know what entrepreneurship is about and that also means I can finance the Purtiso start-up. Chemistry costs a lot of money. The step of taking knowledge and technology from the university and turning it into a business is not cheap, nor is it easy. That is perhaps what makes it unique: that I can combine technological knowledge with experience as an entrepreneur. These two facets are essential because chemistry on the one hand and the business case on the other are actually in constant dialogue. It is a strict condition for success in chemistry.”
“The perspective is therefore completely different from that at university. There, you can solve global problems without being obliged to consider whether they are feasible in a market environment. For the sake of research alone, you can put the real world on hold for a moment. And that is useful. If you do want to take the step of turning it into a business, then a whole host of new parameters come into play: logistics, practical implementation, various types of cost prices, etc.”
Moonshot Flanders played an essential role in developing our technology. Moonshot Flanders helps to bring the technology to higher TRLs. Without such a programme, it simply would not happen.
Did Moonshot Flanders play an important role in your research?
Niels Van Velthoven: “Moonshot Flanders played an essential role in developing our technology. More generally, it is no secret that the chemical sector is struggling. In the current context, companies do not have the budgetary scope for moonshots; their R&D must be able to deliver an immediate return. Moonshot Flanders helps to bring the technology to higher TRLs. Without such a programme, it simply would not happen. Moreover, within Moonshot projects, from the Early Stage Innovation (ESI) stage onwards, it becomes mandatory to also think about your innovation in economic terms. That is very important. It immediately steers you in the direction of concrete implementation. In the next step, Later Stage Innovation (LSI) projects enable you to build pilot installations. This allows you to reach TRL6. That is the de-risking that companies need in order to invest in these technologies themselves.”
“I personally believe that university Tech Transfer Offices could improve their role in this regard. Specifically for the chemical industry, the high investment costs for companies and the low margins should be taken more into account. The chemical sector is very different from, for instance, the pharmaceutical sector and I personally believe it requires different solutions in terms of optimal tech transfer. My hope would be that VLAIO and Moonshot Flanders, together with the Tech Transfer Offices can further identify some of the potential difficulties for start-ups.”
Why did you choose to establish Purtiso in Chemelot (NL)?
Niels Van Velthoven: “The challenge of PU recycling is mostly a technological one. At the stage we are currently at, we need to characterise our samples in-depth. Chemelot is unique in the world because DSM's entire characterisation division has been made available to the start-ups here, so I have access to the same analytical tools as the R&D divisions of the major chemical companies like Covestro and BASF. For a start-up, that equipment is unaffordable, but here I can pay per test. In principle, you could also work with universities for your characterisations, but that is a lot slower.”
“Once the pilot phase milestones have been achieved, we can start on the demo plant. That could easily represent an investment of 10 to 20 million euros. Hopefully, we can achieve this in three years. It is definitely an option to do that in Flanders and give something back in return for all the support I have received in my research.”
What source of polyurethane could you use?
Niels Van Velthoven: “Mattress factories, for example, produce a lot of cutting waste. This is very interesting because its composition is known and it does not contain a lot of contaminants. But the dismantling of used mattresses is also gaining momentum. However, we still must wait for better recycling methods. Once these are in place, dismantling will also gain momentum. A third interesting source is refrigerators. These are already being dismantled and contain PU.”
“PU is already being recycled at Dow in France and Repsol in Spain, but these are first-generation technologies and the recycled products are of relatively low quality. We aim for recycled products that are close to virgin quality. That quality enables higher value applications and increases product value, resulting in higher operational margins.”
We are also familiar with Triple Helix, which is also focusing on PU recycling. Are you in a race against time with them?
Niels Van Velthoven: “I think we are more complementary. Their technology has already been de-risked, so we are at different stages of development and technology. Steven Peleman of Triple Helix is a real trailblazer for PU recycling. He was the first to cut a path through the jungle, so to speak, and we can now follow in his footsteps. I am very grateful for that. We are in direct contact and can work together in market creation because we are in the same boat.”
Thank you for this pleasant conversation, Niels. Good luck and keep us informed!