Lignin: Key to the Bioeconomy and Challenges to Scaling

Lignin - a term you might have heard in high school biology, and infrequently since. It’s the binding agent in wood, as well as the world’s second most abundant biopolymer after cellulose  and holds immense potential as a renewable resource for a huge range of applications.

What is lignin, and why should we care?

There is a misconception that it is primarily burned as waste in the paper and pulp industry, which isn’t true, but it has much more potential than what it currently lives up to. In the emerging bioeconomy, lignin could play a crucial role in replacing fossil resources and enabling more sustainable production. But how exactly can it be used, where do current developments stand, and what obstacles hinder its large-scale adoption?

Why is Lignin Relevant to the Bioeconomy?

As it is abundant with billions of tons produced annually -  let’s take a look at the characteristics that are valuable in its use.

• It offers natural UV protection and is an antioxidant. 

In cosmetics, lignin shows great potential as a replacement for fossil-based UV filters, which can affect hormone levels and damage marine ecosystems. Companies like Lignopure provide powdered lignin for the manufacture of skincare products.

• It can be used in aromatic compounds and binders. 

Its complex chemical structure makes lignin suitable for aromatic compounds and binders, e.g., in wood composites or as a substitute for phenolic resins. UPM Biochemicals have developed a lignin based product called WISA BioBond, which replaces at least 50% of the fossil based glue in plywood. 

• It can be helpful in the production of lightweight materials and carbon fibers. 

Lignin can be harnessed in electromobility to produce carbon fibers for lighter and more energy-efficient components. The University of Manchester is currently working with Lixea to scale their solution which produces carbon fiber from lignin. They say their approach cuts production costs by three to five times, when compared to conventional carbon fiber production.

• It can be used in various forms within batteries.

Lignin has also found a wide variety of potential uses in batteries, ranging from the binder to the cathode. Stora Enso have developed a lignin based anode for lithium ion and sodium ion batteries, replacing conventional graphitic anodes.

Current Developments and Perspectives

The landscape and value chain surrounding lignin are rapidly changing. Here are some recent developments and potential future uses for lignin.

• Innovative Lignin Startups and Companies

Companies like Lignopure transform raw lignin into processable forms without further chemical modification, acting as a bridge between biorefineries and industries, particularly cosmetics. Lignopure aims to have its first products on shelves by 2025 and expand its portfolio internationally.

• Growing Infrastructure and Research
  

  • UPM Leuna is building a biorefinery in Germany to actively market lignin.

  • Fraunhofer IGB and CBP are developing new processing technologies.

  • Fibenol focus on sulfur-free lignin, which is more environmentally friendly and of a higher quality. They are currently building a bioprocessing plant in Latvia, with production expected to start in around five years.

One Size does not fit all - lignin’s case

However, despite the incredible potential and developments we’ve just discussed, several challenges hinder lignin's scalability and its ability to replace fossil resources.

• Heterogeneity and Lack of Standardization

Lignin's structure varies widely depending on its source and processing method, with types differing by wood type, location, and climate. This lack of standardization complicates the search for suitable lignin types. A trading platform could help, although companies like Lignopure currently prefer to handle this themselves.

• Chemical Structure and Molecular Size

Its complex chemical structure and large molecular size limit reactivity and complicate processing for industrial applications. Often, chemical modifications or reductions are necessary, which are expensive and complex.

• Regulatory Requirements and Market Access

As a new ingredient in cosmetics and other products, lignin must meet strict regulatory requirements, like ISO 17516. The approval process is costly and lengthy, posing a significant barrier, especially for startups.

• Lack of Risk Appetite and Innovation Among Customers

Lignin is not an immediate solution: it requires new formulations and development. There is a shortage of bold, motivated customers willing to invest in innovative products and take on the associated risks.

Conclusion and Outlook

Lignin has the potential to shape the bioeconomy sustainably and replace fossil resources. However, to realize this potential, the above challenges have to be addressed. To make lignin a game-changer, industry, research, and politics must work together towards a more environmentally friendly and resource-efficient future. 

Here at RootCamp, we’ve been concerning ourselves with the topic of bioeconomy for a while. As a part of this, we have been able to hold two workshops focusing on lignin and industry hemp and publish a report on industry hemp  (with one on lignin coming soon) within our ‘Bioeconomy Deep Dives’ project. The workshops have connected agricultural and industrial stakeholders, with the goal of identifying innovation gaps and potential hurdles together. This has all been made possible through the support from the Bundesministerium für Landwirtschaft, Ernährung, und Heimat (BMLEH) through Rentenbank. Our next bioeconomy event will take place on August 26th in Hannover. Register here to be part!  We will explore how to meet rising demand by boosting biological production, and use resources more efficiently. Together, we’ll develop practical, collaborative solutions for the bioeconomy transition.