“…To tackle the above challenges, researchers should study the reaction process of petroleum components at the molecular level. A series of diesel hydrogenation technologies have been developed to improve diesel quality. − Conventional hydro-refining can merely achieve the target of reducing the sulfur and nitrogen content in diesel, but the increase in CN is small, and it cannot conform with the quality requirement of PAHs, density, and certain other properties, whereas hydro-upgrading containing the main reactions of aromatic hydrogenation saturation and ring opening can effectively reduce the content of PAHs and increase the CN.…”