▎ 摘　　要

NOVELTY - Preparing graphene-modified nanocrystalline cellulose involves adding nanocrystalline cellulose to acetone, reacting for 70-72h at 80-90 degrees C under constant temperature, alternately washing with ethanol and deionized water, drying in vacuum to obtain the pretreated nanocrystalline cellulose. The pretreated nanocrystalline cellulose is added into concentrated nitric acid, and the mixture is dispersed ultrasonically. Then, the reaction mixture is reacted at 80-90 degrees C for 2-3h, washed with deionized water to pH 7.0 and dried under vacuum to obtain acidified nanocrystalline cellulose. USE - Method for preparing graphene-modified nanocrystalline cellulose (claimed). ADVANTAGE - The method enables to prepare graphene-modified nanocrystalline cellulose in simple steps, stable and controllable process with high operability, low cost and high production efficiency, and greatly improves the adsorption performance and adsorption selectivity of the nanocrystalline cellulose. DETAILED DESCRIPTION - Preparing graphene-modified nanocrystalline cellulose involves adding nanocrystalline cellulose to acetone, reacting for 70-72h at 80-90 degrees C under constant temperature, alternately washing with ethanol and deionized water, drying in vacuum to obtain the pretreated nanocrystalline cellulose. The pretreated nanocrystalline cellulose is added into concentrated nitric acid, and the mixture is dispersed ultrasonically. Then, the reaction mixture is reacted at 80-90 degrees C for 2-3h, washed with deionized water to pH 7.0 and dried under vacuum to obtain acidified nanocrystalline cellulose. The acidified nanocrystalline cellulose is mixed with polyamide-amine, reacted for 10-12h at 20-30 degrees C, washed with excess methanol and deionized water, dried in vacuum to constant weight to obtain polyamide - amine modified nanocrystalline cellulose. The oxidized graphene is added into acetone and dispersed by ultrasonic treatment to obtain oxidized graphene dispersion. The polyamide-amine modified nanocrystalline cellulose is added into the oxidized graphene dispersion liquid, and is filtered at 100 degrees C under constant temperature. The filter material is repeatedly washed with ethanol and deionized water, and dried to constant weight to obtain graphene-modified nanocrystalline cellulose.