Scientists launch sustainable lignin-based carbon fiber

Lignin, a widely available by-product of cellulose production, is emerging as a sustainable alternative to petroleum-based carbon fiber. With approximately 70 million tons of lignin generated annually, researchers are unlocking its potential for high-value applications, particularly next-generation carbon fiber manufacturing.

Industry partner Lixea, in collaboration with Imperial College London, developed a patented process that converts lignin into carbon fiber using ionic liquid technology and polyvinyl alcohol (PVA). This innovation enables the production of high-lignin-content fibers (75%–90%) with excellent structure and yield while significantly reducing costs—by up to five times compared to traditional petroleum-based methods.

To scale this technology, researchers at The University of Manchester, led by Professor Jonny Blaker, conducted a pilot-scale demonstration at the Fiber Technology Platform, Henry Royce Institute. Using lignin from Lixea’s pilot plant, the team tested three lignin sources—two from spruce sawdust and one from bagasse (a sugar production by-product). The bagasse-derived lignin proved most effective, allowing for the continuous spinning of fibers for the first time at pilot scale.

The trial successfully produced continuous fibers up to 5 meters long, marking a significant milestone in the development of cost-effective, renewable carbon fiber. Future efforts will focus on refining fiber drying, collection, and carbonization processes, crucial steps toward *commercial-scale production in the U.K.

“We’re excited to demonstrate the scale-up potential of this pioneering process,” said Professor Blaker. “Thanks to our advanced pilot facility, we’ve tackled key formulation and fiber-drying challenges, ensuring compatibility with Lixea’s wood fractionation technology. This marks a major step toward making sustainable carbon fiber a reality.”