▎ 摘　　要

NOVELTY - Preparing a magnetic nitrogen-doped graphene oxide-loaded biochar composite material, comprises washing rice straw with deionized water and then drying. The dried rice straw is placed in a muffle furnace for oxygen-limited calcination, naturally cooled to room temperature, and then sieved after grinding to get sieved sample biochar. The graphene oxide is dissolved in a solvent to obtain a graphene oxide solution, where the concentration of the graphene oxide solution is 0.8g/L. Urea, ferric chloride hexahydrate, and the biochar are added to the graphene oxide solution according to the mass ratio of 5-15:12.5:1:1 under magnetic stirring, transferred into the hydrothermal reactor lined with polytetrafluoroethylene at a certain temperature for a certain time. The obtained product is cooled and vacuum dried to get the magnetic nitrogen-doped graphene oxide and biochar composite material. USE - Method for preparing a magnetic nitrogen-doped graphene oxide-loaded biochar composite material used for adsorbing noble metal ions in an aqueous solution (claimed). ADVANTAGE - The method prepares the magnetic nitrogen-doped graphene oxide-loaded biochar composite material in a simple, cost-effective and eco-friendly manner with certain magnetism, easy recovery after dispersing in a solution. DESCRIPTION OF DRAWING(S) - The drawing shows the magnetic nitrogen-doped graphene oxide-loaded biochar composite material at room temperature with gold ion maximum adsorption capacity. (Drawing includes non-English language text).