Carbon fibers from kraft softwood lignin

The process of forming a carbon fiber from kraft softwood lignin comprising:

• a) acetylating lignin obtained from softwood alkaline black liquor to provide a lignin acetate until the acetyl content of the dry lignin acetate is between 16% and 22% by weight as measured by deacetylation in alkali followed by ion chromatography wherein the lignin acetate melts when heated
• b) melt extruding the acetylated softwood acetylated lignin to provide a coherent “green” lignin fiber
• c) thermally stabilizing the melt extruded green lignin acetate fiber to a state that does not melt on subsequent heating
• d) carbonizing thermally stabilized softwood lignin acetate fiber.