▎ 摘　　要

NOVELTY - Magnetic nano-silica graphene composite material comprises graphene sheets, iron oxide layer loaded on the graphene sheets and nano-silica wrapped around the iron oxide; where the mass ratio of graphene, iron oxide and nano-silica is 4:1:1. USE - The magnetic nano-silica composite graphene is useful for decoloration of methylene blue in treated water (claimed). DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing the magnetic nano-silica graphene composite material, comprising (a) mixing the graphene oxide solid with ethylene glycol solution, ultrasonically dispersing, adding ferric chloride hxahydrate into the mixed solution, ultrasonicating, adding anhydrous sodium acetate, stirring in a constant temperature water bath, adding the solution into autoclave reactor, washing successively with ethanol, washing the precipitate twice with distilled water until pH of the material is 7, vacuum drying, screening the product with the help of an external magnetic field, and collecting the magnetic graphene composite, and (b) dissolving the magnetic graphene composite material in double distilled water to obtain magnetic graphene composite material suspension, adding CTAB and TEOS, adjusting the pH to 8.5 using sodium hydroxide, stirring the mixed solution in a constant temperature water bath and the reacting, then washing the solution with absolute ethanol, washing the precipitate with distilled water until the pH is 7, and vacuum drying; and (2) use of magnetic nano-silica graphene composite material for decoloration of methylene blue in treated water, comprising adding 10-60 mg magnetic graphene nano-silica composite adsorbent into 25 ml 10-100 mg/l methylene blue solution, adjusting the mixture pH to alkaline, and then placing in a constant temperature of 20-40 degrees C shaker, vibrating for 3 hours, and magnetically separating magnetic graphene nano-silica composite to removal methylene blue.