▎ 摘　　要

NOVELTY - A magnetic core shell nanocomposite material comprises oxidized graphene substrate which is loaded with ferroferric-silicon dioxide nanoparticles connected by chitosan. USE - Magnetic core shell nanocomposite material. ADVANTAGE - The nanocomposite material has good adsorption effect and easy recycling. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of magnetic core-shell nanocomposite material comprising: (A) under magnetic force stirring, taking 0.5-1 g polystyrene-maleic acid copolymer sodium salt which is added to 10-20 ml ethylene glycol solvent, stirring and dissolving, adding 0.5-1 g iron (III) chloride hexahydrate with 1-2 g sodium acetate, stirring until it is completely dissolved, transferring the 25-50 ml solution into PTFE liner of stainless steel high pressure hydrothermal reactor, preheating the reactor, placing in an oven at 200 degrees C and reacting for 8-10 hours, taking out the reaction kettle, naturally cooling to room temperature, magnetic separation or centrifuging to separate magnetic particles, using secondary water to remove unreacted reactants and by-products, and vacuum drying at 30-50 degrees C to prepare the ferroferric oxide nanoparticle; (B) dispersing 6-12 ml prepared ferroferric oxide nanoparticle, taking 1-2 ml spare solution into 20-40 ml mixed solution of ethanol, 1-2 ml water and 1-2 ml ammonia water, ultrasonically dispersing it to uniform, adding 0.1-0.2 ml tetraethylorthosilicate and 5-10 ml mixed solution of ethanol, performing ultrasonic reaction for 90 minutes after performing the magnetic separation, washing three times with ethanol to obtain ferroferric oxide (Fe3O4)-silicon dioxide (SiO2) magnetic nanoparticle; (C) preparing graphene oxide by Hummers preparation method; and (D) taking 2-4 g chitosan, dissolving in 1-2 vol.% 100 ml acetic acid solution to prepare 2-4 mass% chitosan solution, and ultrasonically treating for 30 minutes by adding 0.5-1 g Fe3O4-SiO2 magnetic nanoparticle, stirring for 1-2 hours, adding 10-15 ml graphene oxide of 50% glutaraldehyde solution and 1-2 g product obtained in step (C) to the reaction flask, adjusting pH to 9-10, continuing to stir for 1-2 hours at 80 degrees C, washing the precipitate with ethanol or distilled water, and drying at 50-60 degrees C in vacuum to obtain magnetic core shell nanocomposite material.