Iowa State University researchers are developing carbon fiber from two low-value coproducts: softwood kraft lignin from paper production and the watery fraction of bio-oil from fast pyrolysis. The biobased fiber reached a tensile strength of 2.45 GPa and stiffness of 236 GPa, above the Department of Energy's recommended targets for automotive use, while keeping projected costs under $5 per pound. A four-year, $2 million NSF grant will move the process from batch lab production to continuous commercial-scale manufacturing. The project includes Harper International, Latis Materials, and Rise Energy, a startup supplying bio-oil. Researchers also cut the stabilization time for spun fiber from tens of hours to two to four hours, removing a major production bottleneck. If the scale-up works, the process could raise the value of paper and bio-oil production and create a domestic source of high-performance carbon fiber for vehicles, wind energy, and infrastructure.
