The production processes of benzene include catalytic reforming and pyrolysis petrol hydrogenation technology. (1) Benzene production via catalytic reforming: C6--C8 hydrocarbon fractions obtained during petroleum refining are aromatized into aromatic hydrocarbons such as benzene in the presence of catalysts like platinum, followed by separation to obtain pure benzene. (2) Pyrolysis petrol hydrogenation: When pyrolysis petrol is used as a feedstock for aromatic extraction to produce high-purity aromatic products, it must first undergo selective hydrogenation and hydrotreating to remove impurities such as dienes, alkenyl aromatics, alkenes, as well as sulfur, nitrogen, and oxygen compounds. Currently, the industry widely adopts a two-stage hydrogenation process: the first stage primarily removes dienes and olefinic aromatics, mainly using low-temperature liquid-phase selective hydrogenation technology; the second stage mainly removes mono-olefins as well as impurities such as sulfur, nitrogen, and oxygen, typically employing high-temperature gas-phase hydrofining technology, which involves relatively severe process conditions.