▎ 摘　　要

NOVELTY - Graphene-supported transition metal compound is obtained using graphene oxide as carrier, polyoxometalate as tungsten source and N-containing polymer as carbon and nitrogen source, to prepare graphene oxide-supported polyoxometalate precursor, preparing graphene-supported transition metal carbide, tungsten-doped tungsten nitride or metal tungsten heterogeneous catalyst, loading keggin-type polyoxometalate on polymer-modified graphene oxide, and pyrolyzing. The keggin-type polyoxometalate is phosphotungstic acid hydrate (I) or phosphomolybdate hydrate (II). The polymer-modified graphene oxide is polyethyleneimine-modified graphene oxide, dopamine-modified graphene oxide, chitosan-modified graphene oxide, polypyrrole-modified graphene oxide and/or polyaniline-modified graphene oxide. The graphene-supported tungsten-doped tungsten nitride or metallic tungsten is prepared by loading polyoxometalate (III)-(V) on polymer-modified graphene oxide, and pyrolyzing. USE - Graphene-supported transition metal compound used in desulfurization of fuel oil by catalytic oxidation (claimed). ADVANTAGE - The heterogeneous catalyst has low catalytic activity, and low removing rate of large concentration of sulfur-containing compound in fuel. The obtained catalyst has excellent chemical stability, low cost, environmentally-friendly and high catalytic performance. The catalyst is capable of accelerating speed of desulfurization, and improving stability. DETAILED DESCRIPTION - Graphene-supported transition metal compound is obtained using graphene oxide as carrier, polyoxometalate as tungsten source and N-containing polymer as carbon source and nitrogen source, to prepare graphene oxide-supported polyoxometalate precursor by electrostatic bonding, preparing graphene-supported transition metal carbide, tungsten-doped tungsten nitride or metal tungsten heterogeneous catalyst by high-temperature pyrolysis, where the transition metal carbide is tungsten carbide or molybdenum carbide and the tungsten-doped tungsten nitride is tungsten-tungsten nitride, preparing graphene-supported transition metal carbide heterogeneous catalyst by loading keggin-type polyoxometalate on polymer-modified graphene oxide using electrostatic bonding method, and pyrolyzing at high temperature. The keggin-type polyoxometalate is phosphotungstic acid hydrate (PW12) of formula: H3PW12O40.xH2O (I) or phosphomolybdate hydrate (PMo12) of formula: H3PMo12O40.xH2O (II). The polymer-modified graphene oxide is at least one of polyethyleneimine-modified graphene oxide (PEI/GO), dopamine-modified graphene oxide (PDA/GO), chitosan-modified graphene oxide (CS/GO), polypyrrole-modified graphene oxide (PPy/GO), and polyaniline-modified graphene oxide (PANI/GO). The graphene-supported tungsten-doped tungsten nitride or metallic tungsten is prepared by loading Keggin-type or Dawson-type polyoxometalate on polymer-modified graphene oxide by electrostatic bonding, and pyrolyzing at high temperature. The keggin-type polyoxometalate is silicotungstic acid hydrate (SiW12) of formula: H4SiW12O40.xH2O (III), and the dawson-type phosphotungstate hydrate is potassium phosphotungstate hydrate (P2W18) or (P2W17) of formulae: K6(alpha-P2W18O62).14H2O (IV) or K10(alpha-P2W17O61).20H2O (V). INDEPENDENT CLAIMS are included for the following: 1. preparation of the graphene-supported transition metal compound, which involves: a. adding 0.05-0.3 g of polymer-modified graphene oxide to 10-60 mL of water, acidifying and making first liquid; b. dissolving 0.2-0.6 g of polyoxometalate in 10-20 mL of deionized water and acidifying to form second liquid; c. adding second liquid slowly to first liquid, adjusting pH of the solution to 4-5, reacting at room temperature for 10-12 hours, centrifuging at 25degrees Celsius under 4000 rpm for 10-15 minutes to obtain solid product, washing with deionized water, and freeze-drying in vacuum at -55degrees Celsius for 48 hours to obtain polymer-modified graphene oxide supported polyoxometalate; d. placing 0.1-0.4 g of the prepared polymer-modified graphene oxide supported polyoxometalate in a porcelain boat, under a nitrogen atmosphere, heating up to 800-1000degrees Celsius at a rate of 5degrees Celsius/minute and keeping warm for 2 hours to obtain graphene-supported transition metal carbide, tungsten-doped tungsten nitride and metal tungsten heterogeneous catalyst; 2. application of the graphene-supported transition metal compound in desulfurization of fuel oil by catalytic oxidation, which involves: a. catalyzing oxidative desulfurization of dibenzothiophene under normal pressure using hydrogen peroxide as oxidant, graphene-supported transition metal carbide, tungsten-doped tungsten nitride or metallic tungsten as heterogeneous catalyst, where the oxidation product is dibenzothiophene sulfone.