Continuously processing waste lignin into high-value carbon nanotube fibers

High value utilization of renewable biomass materials is of great significance to the sustainable development of human beings. For example, because biomass contains large amounts of carbon, they are ideal candidates for the preparation of carbon nanotube fibers. However, continuous preparation of such fibers using biomass as carbon source remains a huge challenge due to the complex chemical structure of the precursors. Here, we realize continuous preparation of high-performance carbon nanotube fibers from lignin by solvent dispersion, high-temperature pyrolysis, catalytic synthesis, and assembly. The fibers exhibit a tensile strength of 1.33 GPa and an electrical conductivity of 1.19 × 10⁵S m^-1, superior to that of most biomass-derived carbon materials to date. More importantly, we achieve continuous production rate of 120 m h^-1. Our preparation method is extendable to other biomass materials and will greatly promote the high value application of biomass in a wide range of fields.