Process for the preparation of group ii and group iii lube base oils

Abstract

A process for the preparation of Group II and Group III lube oil base stocks wherein liquid-continuous aromatics saturation is used to treat lube hydrocrackate. The treated hydrocrackate is then be sent to dewaxing unit and then optionally to a hydrotreating step.

1 . A process for the production of high quality lube base oils, which process comprising:
 i) hydrocracking a lube oil feedstock having a boiling point above 600° F. and containing polycyclic aromatics in the presence of hydrogen and a hydrocracking catalyst to produce a hydrocrackate having a boiling point above 600° F. which hydrocrackate contains a lesser amount of polycyclic aromatics than said lube oil feedstock;   ii) hydrotreating at least a portion of said hydrocrackate in the presence of an aromatics saturation catalyst under effective aromatics saturation conditions in a liquid-continuous reactor to form a hydrotreated hydrocrackate having a waxy paraffinic component; and   iii) catalytically dewaxing said hydrotreated hydrocrackate in the presence of hydrogen and a dewaxing catalyst under effective dewaxing conditions including a temperature from 500° F. to 750° F. and a pressure up to 2200 psig and at an effective contact time of feed to catalyst that will remove at least a portion of the waxy paraffinic components by isomerization to less waxy iso-paraffinic components, thereby producing a lube base oil containing of at least 90 wt. % saturates, less than 0.03 wt. % sulfur and a viscosity index of at least 80.   
     
     
         2 . The process of  claim 1  wherein the lube oil feedstock is selected from the group consisting of vacuum gas oils, hydrocracked gas oils, hydrocracked vacuum gas oils, deasphalted oils, slack waxes, foots oils, coker tower bottoms, reduced crude, vacuum tower bottoms, deasphalted vacuum resids, fluid catalytic cracking tower bottoms, and cycle oils. 
     
     
         3 . The process of  claim 2  wherein the lube oil feedstock is a vacuum gas oil. 
     
     
         4 . The process of  claim 1  wherein a portion of the hydrotreated hydrocrackate is recycled to the liquid-continuous reactor and again hydrotreated with fresh hydrocrackate. 
     
     
         5 . The process of  claim 4  wherein the volume ratio of recycled hydrotreated hydrocrackate to fresh hydrocrackate to the liquid-continuous reactor is from 0.5 to 1 to 5 to 1. 
     
     
         6 . The process of  claim 4  wherein the volume ratio of recycled hydrotreated hydrocrackate to fresh hydrocrackate to the liquid-continuous reactor is from 1 to 1 to 3 to 1. 
     
     
         7 . The process of  claim 1  wherein a portion of the hydrotreated hydrocrackate from the liquid-continuous reactor is withdrawn and saturated with hydrogen then recycled back to the liquid-continuous reactor. 
     
     
         8 . The process of  claim 1  wherein the aromatics saturation catalyst is comprised of one or more catalytic metals selected from Groups VIB and Group VIII of the Periodic Table of the Elements on an amorphous or crystalline refractory support. 
     
     
         9 . The process of  claim 8  wherein the support is a mesoporous material. 
     
     
         10 . The process of  claim 9  wherein the mesoporous material is MCM-41. 
     
     
         11 . The process of  claim 9  wherein the catalytic metal is selected from the group consisting of Pt and Pd. 
     
     
         12 . The process of  claim 1  wherein the hydrocracking of step i) results in at least a 50% reduction of aromatics compared to the amount of aromatics in the lube oil feedstock. 
     
     
         13 . The process of  claim 1  wherein the process conditions for aromatics saturation during hydrotreating includes temperatures from 400° F. to 750° F. and pressures from 500 psig to 2500 psig. 
     
     
         14 . The process of  claim 1  wherein the catalytic dewaxing temperature is from 500° F. to 750° F. 
     
     
         15 . The process of  claim 1  wherein the catalytic dewaxing catalyst is selected from the group consisting of crystalline aluminosilicates and silicoaluminophosphates. 
     
     
         16 . The process of  claim 15  wherein the catalytic dewaxing catalyst is a crystalline aluminosilicate selected from the group consisting of ZSM-22, ZSM-23, ZSM-35 and ZSM-48, and combinations thereof. 
     
     
         17 . The process of  claim 16  wherein the catalytic dewaxing catalyst contains a binder material selected from the group consisting of alumina, titania, silica, silica-alumina, zirconia, and combinations thereof. 
     
     
         18 . The process of  claim 16  wherein the catalytic dewaxing catalyst contains at least one metal selected from the group consisting of Pt, Pd, and Ni. 
     
     
         19 . The process of  claim 18  wherein the catalytic dewaxing catalyst also contains a metal selected from W and Mo. 
     
     
         20 . The process of  claim 1  wherein the dewaxed lube oil is subjected to hydrofinishing in the presence of hydrogen and a hydrofinishing catalyst at a temperature from 300° F. to 675° F. and total pressures from 400 to 3000 psig. 
     
     
         21 . The process of  claim 20  wherein the hydrofinishing catalyst is comprised of one or more metals selected from Group VIII and Group VIB of the Periodic Table of the Elements. 
     
     
         22 . The process of  claim 21  wherein the hydrofinishing catalyst contains at least one metal from Group VIII and at least one metal from Group VIB. 
     
     
         23 . The process of  claim 21  wherein the hydrofinishing catalyst is comprised of a noble metal selected from Pt and Pd on a mesoporous crystalline support. 
     
     
         24 . The process of  claim 23  wherein the mesoporous crystalline support is MCM-41. 
     
     
         25 . A process for the production of high quality lube base oils, which process comprising:
 i) hydrocracking a lube oil feedstock having a boiling point above 600° F. and containing polycyclic aromatics in the presence of hydrogen and a hydrocracking catalyst to produce a hydrocrackate having a boiling point above 600° F. which contains a lesser amount of polycyclic aromatics than said lube oil feedstock;   ii) hydrotreating at least a portion of said hydrocrackate in the presence of an aromatics saturation catalyst under effective aromatics saturation conditions in a liquid-continuous reactor to form a hydrotreated hydrocrackate having a waxy paraffinic component;   iii) catalytically dewaxing said hydrotreated hydrocrackate in the presence of hydrogen and a dewaxing catalyst under effective dewaxing conditions including a temperature from 500° F. to 750° F. and a pressure up to 2200 psig and at an effective contact time of feed to catalyst that will remove at least a portion of the waxy paraffinic components by isomerization to less waxy iso-paraffinic components; and   iv) subjecting the dewaxed hydrotreated hydrocrackate to hydrofinishing in the presence of hydrogen and a hydrofinishing catalyst and at hydrofinishing conditions thereby resulting in a lube base oil comprised of at least 90 wt. % saturates, less than 0.03 wt. % sulfur and a viscosity index of at least 80.   
     
     
         26 . The process of  claim 25  wherein the lube oil feedstock is selected from the group consisting of vacuum gas oils, hydrocracked gas oils, hydrocracked vacuum gas oils, deasphalted oils, slack waxes, foots oils, coker tower bottoms, reduced crude, vacuum tower bottoms, deasphalted vacuum resids, fluid catalytic cracking tower bottoms, and cycle oils. 
     
     
         27 . The process of  claim 26  wherein the lube oil feedstock is a vacuum gas oil. 
     
     
         28 . The process of  claim 26  wherein a portion of the hydrotreated hydrocrackate is recycled to the liquid-continuous reactor and again hydrotreated with fresh hydrocrackate. 
     
     
         29 . The process of  claim 28  wherein the volume ratio of recycled hydrotreated hydrocrackate to fresh hydrocrackate to the liquid-continuous reactor is from 0.5 to 1 to 5 to 1. 
     
     
         30 . The process of  claim 28  wherein the volume ratio of recycled hydrotreated hydrocrackate to fresh hydrocrackate to the liquid-continuous reactor is from 1 to 1 to 3 to 1. 
     
     
         31 . The process of  claim 25  wherein a portion of the hydrotreated hydrocrackate from the liquid-continuous reactor is withdrawn and saturated with hydrogen then recycled back to the liquid-continuous reactor. 
     
     
         32 . The process of  claim 25  wherein the aromatics saturation catalyst is comprised of one or more catalytic metals selected from Groups VIB and Group VIII of the Periodic Table of the Elements on an amorphous or crystalline refractory support. 
     
     
         33 . The process of  claim 32  wherein the support is a mesoporous material. 
     
     
         34 . The process of  claim 33  wherein the mesoporous material is MCM-41. 
     
     
         35 . The process of  claim 33  wherein the catalytic metal is selected from the group consisting of Pt and Pd. 
     
     
         36 . The process of  claim 25  wherein the hydrocracking of step i) results in at least a 50% reduction of aromatics compared to the amount of aromatics in the lube oil feedstock. 
     
     
         37 . The process of  claim 25  wherein the process conditions for aromatics saturation during hydrotreating includes temperatures from 400° F. to 750° F. and pressures from 500 psig to 2500 psig. 
     
     
         38 . The process of  claim 25  wherein the catalytic dewaxing temperature is from 500° F. to 750° F. 
     
     
         39 . The process of  claim 25  wherein the catalytic dewaxing catalyst are selected from the group consisting of crystalline aluminosilicates and silicoaluminophosphates. 
     
     
         40 . The process of  claim 39  wherein the catalytic dewaxing catalyst is a crystalline aluminosilicate selected from the group consisting of ZSM-22, ZSM-23, ZSM-35 and ZSM-48, and combinations thereof. 
     
     
         41 . The process of  claim 40  wherein the catalytic dewaxing catalyst contains a binder material selected from the group consisting of alumina, titania, silica, silica-alumina, zirconia, and combinations thereof. 
     
     
         42 . The process of  claim 40  wherein the catalytic dewaxing catalyst contains at least one metal selected from the group consisting of Pt, Pd, and Ni. 
     
     
         43 . The process of  claim 42  wherein the catalytic dewaxing catalyst also contains a metal selected from W and Mo. 
     
     
         44 . The process of  claim 25  wherein the hydrofinishing catalyst is comprised of one or more metals selected from Group VIII and Group VI of the Periodic Table of the Elements. 
     
     
         45 . The process of  claim 44  wherein the hydrofinishing catalyst contains at least one metal from Group VIII and at least one metal from Group VIB. 
     
     
         46 . The process of  claim 44  wherein the hydrofinishing catalyst is comprised of a noble metal selected from Pt and Pd on a mesoporous crystalline support. 
     
     
         47 . The process of  claim 46  wherein the mesoporous crystalline support is MCM-41.