The invention discloses a method for hydro-upgrading inferior catalytic
gasoline. The method comprises the following steps: (1) mixing catalytic
gasoline and
hydrogen and feeding the mixture into a pre-hydrogenating reactor; (2) feeding a product of the step (1) into a fractionating
tower and dividing the product into a light
gasoline component, a medium gasoline component and a heavy gasoline component; (3) taking the light gasoline component discharged from the top of the fractionating
tower as an upgraded gasoline blending component, mixing the medium gasoline component discharged from a side line and the
hydrogen, feeding the mixture into a first
hydrogen desulfurization reactor, reacting and then returning the product to the fractionating
tower; (4) mixing the heavy gasoline component discharged from the bottom of the fractionating tower and the hydrogen, feeding the mixture into a hydro-upgrading reactor and reacting; (5) feeding the product of the step (4) into a second hydrogen desulfurization reactor and reacting; and (6), after the product of the step (5) is cooled down, feeding the product into a product separator and carrying out gas-liquid separation, recycling the hydrogen on the top, feeding a
liquid phase at the bottom into a stabilizer to remove sulfurous gas, and mixing the
liquid phase with light gasoline to obtain the upgraded gasoline product. According to the method, while the content of olefin and the content of sulphur are greatly reduced, loss of
octane value in hydro-upgrading of the catalytic gasoline is reduced.