▎ 摘　　要

NOVELTY - A biomass-based graphene quantum dot is prepared by dissolving 2-aminobenzenesulfonic acid or para-toluenesulfonic acid in deionized water, heating to 70-90 degrees C, stirring uniformly, adding alkali lignin, heat preserving at 70-90 degrees C, filtering the solution with aqueous filter membrane, collecting filtrate, adding alkali solution to filtrate for ultrasonically processing, and carrying out hydrothermal reaction at 180-220 degrees C, filtering using aqueous filter, collecting the filtrate, placing in cut-off dialysis bag, dialyzing with deionized water, and lyophilizing. USE - Biomass-based graphene quantum dot used for illuminating anti-counterfeiting (claimed), and in food and medicine. ADVANTAGE - The biomass-based graphene quantum dot prepared is simple, effective and economical, and does not require high temperature thermal cracking process. The preparation process is simple, safe and has short process flow. The biomass-based graphene quantum dots prepared have excellent biocompatibility, low biotoxicity and excellent photoluminescence properties. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of biomass-based graphene quantum dot, which involves (1) dissolving 2-aminobenzenesulfonic acid or para-toluenesulfonic acid in deionized water, heating to 70-90 degrees C, stirring uniformly, adding alkali lignin, heat preserving at 70-90 degrees C, filtering the solution with aqueous filter membrane, collecting filtrate, adding alkali solution to filtrate for ultrasonically processing, and carrying out hydrothermal reaction at 180-220 degrees C to obtain solution (A), (2) and filtering solution (A) using aqueous filter, collecting the filtrate, placing in trapped dialysis bag, dialyzing with deionized water, and freeze-drying.