▎ 摘　　要

NOVELTY - Graphene separation method involves mixing high purity graphite flakes, concentrated sulfuric acid, nitric acid and concentrated phosphoric acid, heating at 20-100 degrees C for 16 hours, washing, filtering, drying at 25-300 degrees C for 12-96 hours, adding concentrated sulfuric acid, nitrate and oxidizing agent, reacting at 5-60 degrees C for 1-20 hours, diluting with ultrapure water, adding hydrogen peroxide, neutralizing, washing with water, concentrating to produce graphene oxide sol, adding reducing agent, and forming graphene sheet. USE - Graphene separation method (claimed). ADVANTAGE - Graphene is separated efficiently and economically. DETAILED DESCRIPTION - Graphene separation method involves mixing high purity graphite flakes, concentrated sulfuric acid, nitric acid and concentrated phosphoric acid in weight ratio of 1:1-100:1-20:1-20, heating at 20-100 degrees C for 16 hours, washing with ultrapure water, filtering, drying at 25-300 degrees C for 12-96 hours, adding concentrated sulfuric acid, nitrate and oxidizing agent, reacting at 5-60 degrees C for 1-20 hours, diluting with ultrapure water, adding hydrogen peroxide, neutralizing, washing with water, concentrating to produce graphene oxide sol, adding reducing agent, and forming graphene sheet of different diameter.