Catalyst and method for fuels hydrocracking

摘要

Fuels hydrocracking can be used to generate a variety of product slates. Varying the temperature can allow an amount of naphtha product and an amount of unconverted product to be varied. The method can be enabled by a hydrocracking catalyst that includes a combination of metals with activity for hydrodesulfurization.

主权项

1. A method for producing a naphtha product and an unconverted product, comprising:
exposing a first feedstock to a first hydrocracking catalyst in a first reaction vessel under first hydrocracking conditions to form a first hydrocracked effluent including at least a first liquid phase portion, at least about 60 wt % of the first feedstock boiling above about 400° F. (about 204° C.) and at least about 60 wt % of the first feedstock boiling below about 650° F. (about 343° C.), the first hydrocracking catalyst comprising Ni, Mo, and W on an acidic support, the ratio of Mo to W being from about 2:1 to about 1:2, the first reaction vessel further containing a dewaxdewaxing catalyst; fractionating the first liquid phase portion and at least a portion of a second liquid phase portion to form a first naphtha fraction and a first unconverted fraction, the first naphtha fraction corresponding to at least about 80 wt % of the first feedstock and having a final boiling point of about 400° F. (about 204° C.) or less; withdrawing a portion of the first unconverted fraction as a first unconverted product, a weight of the withdrawn first unconverted product corresponding to from about 5 wt % to about 15 wt % of the first feedstock, the withdrawn first unconverted product having an initial boiling point of at least about 400° F. (about 204° C.); separating at least a portion of the remaining portion of the first unconverted fraction as a second feedstock; exposing the second feedstock to a second hydrocracking catalyst in a second reactor vessel under second hydrocracking conditions to form a second hydrocracked effluent including at least the second liquid phase portion; and separating the second hydrocracked effluent to produce the second liquid phase portion; wherein the temperature of the second hydrocracking conditions is at least about 20° F. (11° C.) less than the temperature of the first hydrocracking conditions, and wherein the temperature of the first hydrocracking conditions at start-of-run is less than about 710° F. (377° C.).