▎ 摘　　要

NOVELTY - Preparation of graphene, involves milling graphite powder, mixing sulfuric acid, nitric acid and phosphoric acid in reactor (A) comprising graphite powder, mixing graphite powder and acid mist solution, introducing the mixed solution into reactor (B) comprising sodium nitrate and potassium permanganate, heating the mixture and adding deionized water and stirring, adding hydrogen peroxide, centrifuging mixture, to obtain graphite oxide, dispersing graphite oxide in deionized water, adding hydrazine hydrate, rinsing the mixture with water and methanol, and drying to obtain graphene. USE - Preparation of graphene by acid mist-based graphite milling. ADVANTAGE - The graphene of 99.9% purity is obtained. The high quality graphene is obtained by reduction of highly dispersed graphite oxide. DETAILED DESCRIPTION - Preparation of graphene, involves feeding 1 kg of 8000 mesh graphite powder into the air mill through the fan, and milling for 1-24 hours, then feeding overflow lighter graphite to the reactor (A), mixing sulfuric acid, nitric acid and phosphoric acid at mass ratio of 10:1:1 in reactor (A) comprising graphite powder, mixing graphite powder and acid mist solution at mass ratio of 1:10-1:100, then controlling the temperature to less than 5 degrees C, and continuing mixing, to obtain a mixed solution, introducing the mixed solution into reactor (B) comprising sodium nitrate and potassium permanganate at mass ratio of 1:100, maintaining the reaction temperature to 5 degrees C for 1-4 hours, then adding water and heating at 35-45 degrees C, and reacting for 1-2 hours, continuing to heat the mixture at 90-100 degrees C and adding deionized water, after 10-60 minutes of reaction, stopping heating and continuing stirring for 60 minutes, adding 5 kg of hydrogen peroxide, stopping heating and continuing stirring for 60 minutes, centrifuging the mixture for 1-10 minutes, after rinsing, and drying at 50-70 degrees C, to obtain graphite oxide, dispersing 1kg of graphite oxide in 1 m3 deionized water for 1-2 hours, then adding 18-30 L hydrazine hydrate, and reacting at 60-90 degrees C for 10-20 hours, then suction filtering the mixture and rinsing with water and methanol for 3-4 times, and drying the mixture, to obtain graphene. The concentration of sulfuric acid is 98%, the concentration of nitric acid is 65%, and the concentration of phosphoric acid is 85%.