| 摘要 |
A method for producing monocyclic aromatic hydrocarbons includes a cracking/reforming reaction step of introducing the feedstock oil into a cracking/reforming reactor, bringing the feedstock oil into contact with the catalyst, and causing the feedstock oil to react, thereby obtaining a product, a purification/recovery step of purifying and recovering the monocyclic aromatic hydrocarbons separated from the product produced in the cracking/reforming reaction step, a hydrogenation reaction step of hydrogenating a heavy fraction separated from the product produced in the cracking/reforming reaction step, and a recycling step of returning a hydrogenation reactant of the heavy fraction obtained in the hydrogenation reaction step to the cracking/reforming reaction step. In the recycling step, the hydrogenation reactant of the heavy fraction is introduced at a location different from an introduction location of the feedstock oil into the cracking/reforming reactor so that a time during which the hydrogenation reactant of the heavy fraction is in contact with the catalyst for monocyclic aromatic hydrocarbon production in the cracking/reforming reactor becomes shorter than a time during which the feedstock oil is in contact with the catalyst for monocyclic aromatic hydrocarbon production in the cracking/reforming reactor. |
