▎ 摘　　要

NOVELTY - Preparing magnetic graphene composite material comprises (i) mixing an aqueous solution of iron(III) chloride having a concentration of less than 0.15 mol-L with an aqueous solution of sodium hydrogencarbonate having a concentration of less than or equal to 0.5 mol-L to obtain a first mixed solution, (ii) mixing an aqueous solution of ascorbic acid with an aqueous solution of graphene oxide to obtain a second mixed solution and (iii) reacting the first mixed solution and the second mixed solution, where then mass ratio of the ascorbic acid, iron(III) chloride and graphene oxide is (0.1-0.72):0.65 (0.04-0.12). USE - The material useful in vegetable fats and oils (claimed). ADVANTAGE - The material involves less reagent species, good biological compatibility, and the method is simple and easy to realize magnetic graphene composite material prepared capable of efficient absorption in vegetable fat of benzo (a) pyrene impurities. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing magnetic graphene composite material prepared by above method; and (2) use of the magnetic graphene composite material as a benzo(a)pyrene adsorbent is preferably used as a benzo(a)pyrene adsorbent in vegetable fats and oils.