| 摘要 |
The instant invention discloses a process of upgrading a waxy hydrocarbon feed mixture containing sulfur compounds which boils in the distillate range, in order to reduce sulfur content and 85% point while preserving the high octane of naphtha by-products and maximizing distillate yield. The process employs a single, downflow reactor having at least two catalyst beds and an inter-bed redistributor between the beds. The top bed contains a hydrocracking catalyst, preferably zeolite beta, and the bottom bed contains a dewaxing catalyst, preferably ZSM-5. A desulfurization catalyst may be added to either bed depending on sulfur distribution in the feed. The feed is separated into a lighter, lower boiling stream and a heavier, higher boiling stream. The effluent of the top bed cascades without interbed separation to the inter-bed redistributor, where it is recombined with the lighter stream. The recombined stream then enters the bottom bed for dewaxing. The product comprises a distillate having an increased yield and a naphtha having an increased research octane number, as compared with a feedstock in which the entire stream was hydrocracked.
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