Lubricant basestock production with enhanced aromatic saturation

Abstract

Systems and methods are provided for producing lubricant basestocks having a reduced or minimized aromatics content. A first processing stage can perform an initial amount of hydrotreating and/or hydrocracking. A first separation stage can then be used to remove fuels boiling range (and lower boiling range) compounds. The remaining lubricant boiling range fraction can then be exposed under hydrocracking conditions to a USY catalyst including a supported noble metal, such as Pt and/or Pd. The USY catalyst can have a desirable combination of catalyst properties, such as a unit cell size of 24.30 or less (or 24.24 or less), a silica to alumina ratio of at least 50 (or at least 80), and an alpha value of 20 or less (or 10 or less). In some aspects, the effluent from the second (hydrocracking) stage can be dewaxed without further separation. In such aspects, a portion of the dewaxed effluent can be used as a recycle quench stream to cool the hydrocracking effluent prior to entering the dewaxing reactor.

1 .- 13 . (canceled) 
     
     
         14 . A system for producing a lubricant boiling range product, comprising:
 a hydrotreating reactor comprising a hydrotreating feed inlet, a hydrotreating effluent outlet, and at least one fixed catalyst bed comprising a hydrotreating catalyst;   a separation stage having a first separation stage inlet and a second separation stage inlet, the first separation stage inlet being in fluid communication with the hydrotreating effluent outlet, the separation stage further comprising a plurality of separation stage liquid effluent outlets, one or more of the separation stage liquid effluent outlets corresponding to product outlets;   a hydrocracking reactor comprising a hydrocracking feed inlet, a hydrocracking effluent outlet, and at least one fixed catalyst bed comprising a hydrocracking catalyst, the hydrocracking feed inlet being in fluid communication with at least one separation stage liquid effluent outlet, and the hydrocracking catalyst comprising USY zeolite having a unit cell size of 24.30 Å or less, a silica to alumina ratio of at least 50, and an Alpha value of 20 or less, the hydrocracking catalyst further comprising 0.1 wt % to 5.0 wt % of a Group 8-10 noble metal supported on the hydrocracking catalyst; and   a dewaxing reactor comprising a dewaxing feed inlet, a dewaxing effluent outlet, and at least one fixed catalyst bed comprising a dewaxing catalyst, the dewaxing feed inlet being in fluid communication with the hydrocracking effluent outlet and being in fluid communication with the dewaxing effluent outlet.   
     
     
         15 . The system of  claim 14 , wherein the dewaxing reactor further comprises a fixed bed comprising a hydrofinishing catalyst, wherein the hydrotreating reactor further comprises a fixed bed comprising a hydrocracking catalyst, or a combination thereof. 
     
     
         16 . The system of  claim 14 , further comprising a hydrofinishing reactor comprising a hydrofinishing feed inlet, a hydrofinishing effluent outlet, and at least one fixed catalyst bed comprising a hydrofinishing catalyst, the hydrofinishing feed inlet being in direct fluid communication with the dewaxing feed outlet, the dewaxing feed inlet being in direct fluid communication with the hydrofinishing effluent outlet and in indirect fluid communication with the dewaxing effluent outlet. 
     
     
         17 . The system of  claim 14 , the system further comprising an additional hydrocracking reactor comprising an additional hydrocracking feed inlet, an additional hydrocracking effluent outlet, and at least one fixed catalyst bed comprising an additional hydrocracking catalyst, the additional hydrocracking reactor providing indirect fluid communication between the hydrotreating effluent outlet and the first separation stage inlet, the additional hydrocracking feed inlet being in fluid communication with the hydrotreating effluent outlet, the additional hydrocracking effluent outlet being in fluid communication with the first separation stage inlet.