International Day of Forests: Forests and Innovation: New Solutions for a Better World.

The Years of Uncertainty

De Candolle’s discovery, however, was just the spark. Lignin’s true nature remained elusive. Its complex structure, a tangled web of molecules, defied easy analysis. Early researchers grappled with its composition and function within plants like pioneers venturing into uncharted territory. Decades passed as lignin lingered on the sidelines, primarily viewed as a waste product in the pulp industry.

But a few true “Biobelievers” persisted. Payen, Schulze, Fremy—names lost to most—their efforts laid the groundwork for understanding lignin. While their tools were primitive, their belief in lignin’s potential was unwavering. They saw not just a stubborn byproduct but a treasure chest of hidden chemical possibilities.

The Age of Waste: A Shift in Mindset

Before the advent of the kraft pulping process, extracting lignin from wood was a laborious, small-scale affair. It was messy and inefficient, and the resulting lignin was often impure. Mills primarily focused on producing cellulose-based pulp, and lignin was seen as a nuisance – with a simple fate: it was burned in the pulp mill’s recovery boilers. 

This offered some practical use, generating energy and helping reclaim pulping chemicals. However, it overlooked lignin’s true potential. Think of it as discarding a whole tree after harvesting only the fruit—it uses a portion of the resource but ignores the vast possibilities.

Two things happened to spark change:

The Environmental Awakening—In the mid-20th century, there was a growing awareness of industrial processes’ negative environmental impacts. Regulations tightened, and a sense of responsibility for waste management developed. Simply discarding lignin was no longer acceptable.

The Oil Crisis—The instability of fossil fuel supplies and fluctuating prices made industries increasingly eager to find alternative feedstocks. They began examining their waste streams with new interest, searching for previously discarded resources.

Driven by a growing awareness of sustainability and fossil fuel limitations, scientists and industry leaders began questioning the old mindset. Could this lignin “waste” be something more? Could lignin become a renewable, versatile source of valuable materials, revolutionizing industries beyond pulp production?

This shift in perception was crucial.

Pioneers of Possibility: The Scientists

The real breakthroughs came slowly. While industries sought solutions, a dedicated group of scientists kept the flame of lignin research alive. Driven by curiosity and a belief in its potential, they continued to push the boundaries of knowledge.

Imagine trying to liberate a single thread from a tightly woven, indestructible tapestry—that’s the struggle scientists face with lignin. Lignin isn’t a separate substance waiting to be collected within a tree’s woody walls. Instead, it forms an intricate alliance with cellulose and other natural polymers, creating a fortress of strength and resilience. This natural defence mechanism makes trees mighty but also makes extracting pure lignin tricky.

From Understanding to Extraction: The Early Battles

The first attempts to pry lignin loose were like attacking that indestructible tapestry with hammers and chisels. Scientists used harsh chemicals, extreme heat, and brute force. These methods worked but had a cost: the damaged, impure lignin was a far cry from the treasure they’d envisioned. Worse still, the process itself was harmful to the environment.

But Biobelievers didn’t surrender. Advances in analytical techniques like spectroscopy and chromatography allowed scientists to peer into lignin’s complex molecular makeup. This was the key breakthrough: They discovered that lignin was far from waste, a rich source of valuable aromatic compounds offering exciting potential for new applications. 

Building on this knowledge, Swedish research institutes like Innventia (now RISE) developed the LignoBoost process, designed to extract and boost valuable lignin from the pulping process efficiently. Furthermore, this new method is far kinder to the environment, reflecting the growing sustainability awareness.

Although initially pioneered in university laboratories, this LignoBoost process required adaptation to the conditions and vast output of a modern pulp mill. Companies like Valmet further refined and commercialized the technology, making lignin extraction possible and efficient within the demands of large-scale operations.

Lignin’s Biobelievers: Mercer and the Modern Era

At Mercer, we recognized lignin’s extraordinary potential and became true Biobelievers.  We invested heavily in both its extraction and its transformation into cutting-edge materials. Our lignin journey began in 2008 by implementation the industrial-scale LignoBoost process, empowering pulp mills to evolve into true biorefineries.  This innovation unlocked lignin’s vast potential for applications ranging from sustainable resins and plastics to water purification and advanced carbon materials.

We deepened our commitment by participating in an international research cluster focused on lignin.  This collaboration accelerated progress, culminating in the 2023 inauguration of the state-of-the-art Mercer Lignin Centre at our Rosenthal am Rennsteig site in Germany.  This landmark facility represents a significant milestone in the lignin revolution.

“At Mercer, we support the idea of a sustainable circular economy and the responsible use of nature,” says Juan Carlos Bueno, CEO of Mercer International. “Our focus on maximizing wood resources naturally led us to explore the often-untapped potential of lignin. The opening of the Lignin Center embodies Mercer’s commitment to a strong bioindustry.”

Spanning approximately 1,000 square meters, the Centre is a powerhouse of innovation.  It houses a fully integrated LignoBoost XS™ pilot plant capable of extracting up to one ton of high-quality lignin daily. The plant’s hardwood and softwood kraft lignin adaptability ensures feedstock versatility. Alongside its extraction capabilities, the Centre boasts storage facilities, control rooms, offices, and laboratory workstations dedicated to analyzing, developing, and modifying lignin.