▎ 摘　　要

NOVELTY - Directly preparing high-quality graphene from biomass comprises (i) pouring prepared biomass waste raw material into crusher, pouring crushed particles into screen for sieving, and taking particles with uniform aperture; (ii) placing processed raw material into fixed bed, and performing pyrolysis reaction under protection of inert atmosphere at 350-1000 degrees C for 0-10 hours with heating speed of 1-50 degrees C/minute to prepare carbonized material; (iii) mixing dried raw material or carbonized material with activating agent; (iv) placing dried raw material, carbonized material or mixed material into fixed bed, and performing activation treatment under inert atmosphere at 700-1800 degrees C for 0-10 hours with heating speed of 1-50 degrees C/minutes to obtain graphene; and (v) taking-out cooled graphene from high-temperature furnace, adding hydrochloric acid or nitric acid or hydrogen fluoride aqueous solution, stirring and washing, rinsing with distilled water, filtering to neutral, and drying graphene. USE - The method is useful for directly preparing high-quality graphene from biomass. ADVANTAGE - The method: saves resource; protects environment; utilizes clean and cheap renewable agricultural and industrial biomass waste as raw material; can change waste into valuable; can partially replace fossil resource used by traditional technology; and increases sustainability of graphene industry. DETAILED DESCRIPTION - Directly preparing high-quality graphene from biomass comprises (i) pouring prepared biomass waste raw material into crusher to crush, pouring crushed particles into screen for sieving, and taking particles with uniform aperture; (ii) placing processed raw material obtained in step (i) into fixed bed, and performing high-temperature pyrolysis reaction under protection of inert atmosphere at 350-1000 degrees C for 0-10 hours with heating speed of 1-50 degrees C/minute to prepare carbonized material; (iii) mixing dried raw material obtained in step (i) or carbonized material obtained in step (ii) with activating agent in mass ratio of 1:0.2-1:8; (iv) placing dried raw material obtained in step (i), carbonized material obtained in step (ii) or mixed material obtained in step (iii) into fixed bed, and performing activation treatment under inert atmosphere at 700-1800 degrees C for 0-10 hours with heating speed of 1-50 degrees C/minutes to obtain graphene; and (v) taking-out cooled graphene from high-temperature furnace, adding 0.5-4 mol/L hydrochloric acid or nitric acid or hydrogen fluoride aqueous solution, stirring and washing, rinsing with distilled water, filtering to neutral, and drying graphene at 80-120 degrees C for 12 hours to obtain dry biomass-based graphene.