▎ 摘　　要

NOVELTY - Large-size biomass graphene comprises natural biomass as raw material and prepared by mechanical crushing, chemical stripping, carbonization and organic solvent ultrasonic processes and the loose and porous biomass graphene with a sheet diameter greater than 100 mu m is prepared. USE - Used as large-size biomass graphene. ADVANTAGE - The method is simple and easy, and requires low equipment, and has low production cost, and achieves mass production. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the large-size biomass graphene, comprising (i) cleaning and mechanically crushing the natural biomass raw materials into granules, where the particle size is in 20-60 mesh; (ii) adding 1-50 g crushed raw material particles into chemical stripping liquid A and soaking for 1 hour, sonicating for 1-24 hours at room temperature, filtering out the solid matter, and rinsing the filtrate with water; (iii) adding the cleaned filtrate into a tube furnace for carbonization, and controlling the heating rate of the tube furnace at 5-20 degrees C/minute, heating to 200-650 degrees C for 1-10 hours and obtaining carbonized product; and (iv) adding 1-30 g carbonized product into organic solvent B, soaking for 0.5 hours, sonicating for 1-12 hours at room temperature, adding the solid-liquid mixture after ultrasound into the oven, keeping at 60-140 degrees C for 0.5-10 hours, controlling the solid content of 50-95%, and obtaining the biomass graphene with sheet diameter more than 100 mu m.