▎ 摘　　要

NOVELTY - Preparation of high purity crystalline graphite involves (s1) crushing and pressing a biomass raw material into biomass particles, carbonizing to obtain biomass carbon, and conveying carbon into molten iron in crystalline graphite production equipment, (s2) raising the temperature of the molten iron to increase the carbon content of the molten iron, and rapidly lowering the temperature of the molten iron to promote the carbon in the molten iron to be rapidly precipitated to form crystalline graphite and float on the surface of the molten iron, and (s3) collecting the crystalline graphite floating on the surface of the molten iron, removing impurities in crystalline graphite using a mode of combining ultrasonic treatment and flotation, and further purifying using an acid leaching method. USE - Preparation of high purity crystalline graphite used for producing lithium ion battery, refractory material, lubricant, brake sheet, pencil, solar cell, fuel cell and graphene (claimed). ADVANTAGE - The method enables to prepare high-purity crystalline graphite, which has high-quality, and low carbon content of 99.0-99.9%. The method uses renewable biomass as carbon source, using molten iron is capable of continuously recycling as carrier, using green power as energy, realizing continuous low carbon production of high quality crystalline graphite. The method avoids using petroleum coke, natural graphite mineral resource and other non-renewable resources, and realizes zero carbon dioxide emission of carbon source and zero natural environment damage. The molten iron is used as carrier generated by biomass carbon dissolving and crystallization of the carbon in the molten iron.