▎ 摘　　要

NOVELTY - Manufacture of reduced graphene oxide involves pre-treating kish graphite which involves sieving and classifying kish graphite (a) having size of less than 50 mu m and kish graphite (b) having size of 50 mu m or more and removing kish graphite (a), floating kish graphite (b), acid leaching by adding acid in which weight ratio of the acid amount to the kish graphite is 0.25-1.0, oxidizing the pre-treated kish graphite by preparing mixture comprising pre-treated kish graphite, an acid and ammonium nitrate, keeping the mixture at less than 5 degrees C, adding an oxidizing agent, after reaching targeted level of oxidation, adding chemical element to stop the oxidation reaction, optionally separating graphite oxide from the mixture, and exfoliating the graphite oxide into graphene oxide, and reducing graphene oxide. USE - Manufacture of reduced graphene oxide (claimed) used as cooling agent or coating in metal industry. Uses include but are not limited to steel, aluminum, stainless steel, copper, iron, copper alloys, titanium, cobalt, metal composite, nickel industries. ADVANTAGE - The method provides reduced graphene oxide with excellent quality in short time, and with less pollution. The reduced graphene oxide improves the corrosion resistance of metallic substrate. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for reduced graphene oxide, which comprises 20 wt.% oxygen functional groups having average lateral size of less than 30 mu m comprising at least one layer sheet.