▎ 摘　　要

NOVELTY - Preparing carbon nitride-graphene composite material comprises (1) dissolving proper amount of carbon and nitrogen precursor in proper amount of water to prepare a carbon and nitrogen precursor solution, (2) adding proper amount of multilayer graphene oxide into the carbon-nitrogen precursor solution, and dispersing mixture by ultrasonic vibration and stirring, (3) reacting the mixed solution at 50-150degrees Celsius for at least 30 minutes, (4) sequentially centrifuging, filtering and drying the solution after completion of the reaction to obtain a carbon nitride-graphene pyrolysis precursor material, (5) placing carbon nitride-graphene pyrolysis precursor material in a microwave reactor, and rapidly increasing the temperature to 750-1200degrees Celsius for pyrolysis reaction under anoxic or anaerobic conditions, and (6) grinding the pyrolysis reaction product to obtain a finished product. USE - The carbon nitride-graphene composite material is useful in adsorption treatment of rare earth elements in water (claimed). ADVANTAGE - The composite material has simple process, larger specific surface area and better adsorption effect and is economical.