Photocatalytic oxidation desulphurization method

The invention discloses a photocatalytic oxidation desulphurization method, and relates to the technical field of oil refining in the chemical industry. The method includes the steps of mixing fuel oil and an extraction agent in proportion, adding photo-oxidant and catalyst to be stirred, conducting illumination with an ultraviolet high-pressure mercury lamp as the light source, conducting reaction for 3-6 hours at room temperature so the C-S key of a sulfur compound in fuel oil can be broken and S element oxidation polar substances can be dissolved in the extraction agent, and conducting separation removal so that the fuel oil desulphurization aim can be achieved, wherein the catalyst is a silica-gel-supported modified nanometer photocatalyst, the photo-oxidant is hydrogen peroxide, the ultraviolet light source is the 125 w ultraviolet high-pressure mercury lamp, the extraction agent is an N-methyl-2-pyrrolidone (NMP) aqueous solution with volume ratio of 90%, the volume ratio of fuel oil to extracting agent