“We are helping to lay the foundation for a more sustainable chemical industry”
Lignin is a particularly interesting raw material for making the production of aromatics more sustainable, partly because it occurs naturally in abundance. So there is no shortage of potential and that is what VITO is trying to unlock with its pilot installation LignoValue that converts isolated lignin into aromatic building blocks. Thanks to a Moonshot Later stage Innovation trajectory it was able to knit an extension to this. The Pillar II pilot plant is now preparing the lignin by dissolving the lignin in a solvent suitable for further processing via catalytic depolymerisation. A conversation with researcher Kelly Servaes who is in charge of the project.
VITO has been working on lignin as part of its strategic research program since 2013. What exactly is the importance of this feedstock for the chemical industry?
Kelly Servaes: “Aromatics - hydrocarbons with an aromatic character - are important basic chemical products, which today are mainly produced from fossil raw materials. They can be found in many everyday products: clothing, medicines, cosmetics, computers, paint, car parts ... If in the future we can use biomass instead of petroleum to produce aromatics, we will be taking a big step towards greater sustainability. Lignin lends itself perfectly to this. It is a biopolymer found in the cell wall of all kinds of plant cells and is often a residual product in other industrial processes. Through a catalytic process, you can break down lignin into smaller building blocks. These building blocks can be used in a variety applications, polymers and additives, meeting the required specifications towards the market.
The chemical industry is actively looking for ways to become more sustainable. Shouldn't these kinds of innovations happen in the lab of chemical companies?
Kelly Servaes: “A lot of research has already been done on a small scale to add value to lignin. However, the biggest challenge in any innovation project lies in bridging the so-called valley of death: how do you get from lab scale to a commercial process? For an industrial company to scale up such a technology, you have to take an extraordinary amount of risk. That doesn't happen. So we try to be the link between them. A pilot plant that demonstrates in a relevant industrial environment that it can be technically and economically profitable for a concrete product and process. We have started the trajectory of establishing the pilot units with the idea of building a Rolls Royce among the pilot plants, demonstrating difficult processes and conditions, from A to Z. This flexibility, next to continuous processing, is one of the key aspects of our pilot units. The starting point of the design of both pilot units was the possible concept of an industrial scale plant to produce lignin-based building blocks, having the required unit operations. This concept has been downscaled to the size and capacity of the current pilot units, and thus consisting of unit operations scalable to demo and industrial scale.
When starting the scale-up from lab to pilot, adjustments need to be made,. Innovation pathways always encounter many bumps along the road. That's what makes scaling up so difficult.”
“When starting the scale-up from lab to pilot, adjustments need to be made,. Innovation pathways always encounter many bumps along the road. That's what makes scaling up so difficult.”
The LignoValue pilot line was already up and running in 2022. What does the Pillar II pilot project add to that?
Kelly Servaes: “The quality of the lignin coming from industry's waste streams is often not high enough, for example in terms of functionality and reactivity,to make the applications we aim for. We therefore conceived a continuous two-stage process: in a first stage we prepare the lignin by dissolving in a solvent medium, in a second stage the catalysis then takes place. Pillar II is that first step: there we mix the lignin with the solvent and remove the undissolved part. In the development of the process train, solvent recycling, as important factor influencing economics, is considered. The solvent used is recovered from the products. The recovered solvent is again used in the process to assess how many cycles the solvent can be used before negatively influencing the process and resulting product quality. Depending on the lignin source, the characteristics of the derived building blocks will have different characteristics. These characteristics are important toward the development of applications, which need to meet the required specifications. That is exactly why it is so important to have the whole process train together.”
The Pillar II has been operational since the beginning of this year. An important milestone for you personally?
Kelly Servaes: “Installation started here on the exact same day as the LignoValue pilot, but two years apart. It was January and although it doesn’t snow that often in Flanders, at that day it snowed. We all worked together to remove snow and clear the access road for the truck. It was memorable. Over the past few years, as a researcher, to establish the pilot units and the related pilot site I have had to familiarize myself with urban planning regulations, permit files, safety measures, discussions with architects, engineering studies, etc. The site here has become a mini chemical site, as it were, with all the attention that comes with it. Next to the ERDF funding, we could count on the funding from Moonshot. Without it, we might not have gotten the whole process together.”
How far along is it today? Is there a lot of interest? Are any projects already underway?
Kelly Servaes: “Recently we started working in two shifts. That may sound trivial, but it requires some organizational effort, because we are not allowed to run the plants unmanned. We want to eventually demonstrate an operation of at least three days continuously. That's crucial to understand the process parameters that you wouldn't be able to see with shorter operations. Meanwhile, the interest from industry is definitely there. Collaborations with companies, bilateral or research projects, have been established and we are continuously looking for new opportunities. We especially want to collaborate at this stage across the entire value chain, from feedstock to market. Testing different lignin sources in the developed processes and application development are of interest. With the feedback what works for which application we can further improve the process, and thus is very valuable input to map out the next steps. Next to expertise in process development, within the SPOT team – which stands for sustainable polymer technologies - we also have all the knowledge in-house to develop different materials applications. Important in that story is also getting the profitability right. The operations in the pilots should show us the critical factors we need to work on to improve the economic picture as well. In addition, a sustainability assessment is part of the different development, based on the Safe-and-Sustainable-by-Design framework, considering, among others toxicity and environmental assessment.”
What is the ultimate dream with the Pillar II project?
Kelly Servaes: “That within x number of years there will be a demo plant based on the proof-of-concept established with our pilot infrastructure platform. But we have to remember that it took the entire petroleum industry 50 years to get everything right. We cannot expect to have an alternative solution ready in five years.”
“With the current pilot infrastructure platform of LignoValue and PILLAR II we are ready to further elaborate our technology platform, not only focusing on the production of plant-based molecules, but where also chemical recycling of plastics has great potential. In our ambition we want to establish the infrastructure platform and pilot site as a multifunctional platform for technology validation and demonstration.”
“As VITO we collaborate with partners and stakeholders along the value chain, ranging from feedstock providers to application partners to make the lignin-story a success. I believe that with our pioneering work we are helping to lay the foundation for a more sustainable chemical industry.”