Method for producing graphite fibers by catalytic graphitization

The invention provides a method for producing graphite fibers by catalytic graphitization, the method comprises the following steps: taking polyacrylonitrile-based precursor, and pre-oxidizing in air atmosphere; performing low-temperature carbonization; performing high-temperature carbonization; preparing a boron-containing catalyst; soaking the carbonized carbon fibers in a boron-containing catalyst and drying at the temperature of 180-200 DEG C, wherein the drying time is 60-90 s; and graphitizing: graphitizing for 20-40 seconds in an argon atmosphere at the temperature of 2200-2400 DEG C to obtain the graphite fibers. According to the invention, hydrogen chloride gas with a certain concentration is introduced into the carbonization section atmosphere, so that the carbonization time and temperature can be reduced, and the purity of fibers can be improved; meanwhile, the carbonized fiber is impregnated with a boron compound and then graphitized, the graphitization temperature can be reduced, the graphitizati