▎ 摘　　要

NOVELTY - Preparing a layer cryptocrystalline graphene, comprises adding water to be adjusted into the ore slurry with concentration of 30 wt.% with the cryptocrystalline graphite powder with a fixed carbon content of 40-80% and a particle size of 100-200 meshes, adding the intercalating agent and carrying out the first stage grinding to obtain slurry I, diluting the slurry I to 10 wt.%, carrying out the first open-circuit flotation after adding a foaming agent, a collector, an inhibitor and an anionic surfactant to obtain slurry II, concentrating the slurry II to 25 wt.%, carrying out the second stage grinding after adding the intercalating agent, diluting the slurry II to 23 wt.%, adding the intercalating agent, and performing the third stage grinding to obtain the slurry III, diluting slurry III to 8 wt.%, and adding foaming agent, collector, inhibitor and anionic surfactant to conduct second open-circuit flotation to obtain slurry IV, concentrating the slurry IV to 21 wt.%. USE - The layer graphene is useful as lithium battery anode and cathode material, electrical conduction, thermal conductivity material and wave absorbing material (claimed). ADVANTAGE - The method can prepare low-layer crypto-crystalline graphene with high carbon content with low cost.