Catalytic conversion method for producing C6-C8 light aromatic hydrocarbon

The invention relates to a catalytic conversion method for producing C6-C8 light aromatic hydrocarbons, which comprises the following steps: introducing raw oil into a raw material separation unit to obtain a first component rich in polycyclic aromatic hydrocarbons and a second component rich in monocyclic aromatic hydrocarbons; introducing the first component into a hydrotreating unit for hydrogenation reaction, and introducing the obtained hydrogenation component into a catalytic cracking unit; introducing a second component to the catalytic cracking unit; reaction oil gas generated by the catalytic cracking unit is introduced into a product separation unit for separation; introducing the heavy aromatic fraction into the catalytic cracking unit; and introducing the light aromatic hydrocarbon fraction into an aromatic hydrocarbon extraction unit for extraction to respectively obtain C6-C8 light aromatic hydrocarbon and raffinate oil. According to the method, the raw oil can be converted into light aromatic h