Modified nano TiO2 photocatalyst capable of degrading benzene series, and preparation method and application of same

The invention provided a modified nano TiO2 photocatalyst capable of degrading benzene series, and a preparation method and application of the modified nano TiO2 photocatalyst. The modified nano TiO2 photocatalyst is prepared by the following steps: step 1, adding an organic solvent, nanometer TiO2 powder and hexadecyl trimethyl ammonium bromide into a reactor, stirring the mixture to be uniform, heating to increase the temperature up to 90-130 DEG C, dripping epoxide, continuously reacting for 2.5-8.0 hours, cooling liquid reactant after finishing the reaction, dripping a KOH aqueous solution under the condition of stirring, adding water for dissolving generated salt, performing suction filtration, washing filter cakes with distilled water, and drying; step 2, sequentially adding a product obtain in the step 1, a methyl sulfoxide aqueous solution, methylene chloride and a perchloric acid aqueous solution, stirring for 36 hours at room temperature, diluting liquid reactant by ethyl acetate, performing water w