Heavy lube oil from fischer- tropsch wax

Abstract

A heavy lubricant base stock is made by (a) producing a synthesis gas from natural gas, (b) reacting the H 2 and CO in the gas in the presence of a cobalt Fischer-Tropsch catalyst, at reaction conditions effective to synthesize waxy hydrocarbons boiling in the heavy lubricant oil range, which are hydrodewaxed it at least two stages, with interstage separation and removal of the lighter material.

What is claimed is:  
     
         1 . A multistage process for producing a heavy lubricant base stock from Fischer-Tropsch wax comprises hydrodewaxing said wax in a first hydrodewaxing stage to produce an isomerate comprising a partially dewaxed heavy lubricant oil fraction, followed by hydrodewaxing said heavy lubricant oil fraction in one or more successive hydrodewaxing stages, with interstage removal of hydrocarbons boiling below said heavy lubricant oil fraction, to form said heavy lubricant base stock and wherein said hydrodewaxing is achieved in the presence of hydrogen and a hydrodewaxing catalyst that dewaxes by isomerization.  
     
     
         2 . A process according to  claim 1  wherein said heavy lubricant base stock has cloud and pour points lower than that of said heavy fraction in said wax.  
     
     
         3 . A process according to  claim 2  wherein said heavy lubricant oil fraction has an initial boiling point of at least 850° F. (454° C.).  
     
     
         4 . A process according to  claim 3  wherein said heavy lubricant base stock has an initial boiling point in the range of 850-1000° F. (454-538° C.).  
     
     
         5 . A process according to  claim 4  wherein said partially dewaxed heavy lubricant oil fraction hydrodewaxed in said one or more successive hydrodewaxing stages comprises less than 25 wt. % lower boiling hydrocarbons.  
     
     
         6 . A process according to  claim 5  wherein said heavy lubricant base stock has been hydrofinished and optionally dehazed.  
     
     
         7 . A process according to  claim 6  wherein said heavy lubricant base stock is combined with one or more lubricant additives to form a lubricant.  
     
     
         8 . A process according to  claim 7  wherein said heavy lubricant base stock has an end boiling point above 1050° F. (566° C.) and a cloud point no greater than 75° F. (24° C.).  
     
     
         9 . A process according to  claim 8  wherein said catalyst comprises a hydrogenating component, a solid acid component, and a binder.  
     
     
         10 . The process of  claim 9  wherein said solid acid component is selected from the group consisting of ZSM-23, ZSM-35, ZSM-48, ZSM-57, ZSM-22, zeolite beta, mordenite, rare earth ion exchanged ferrierite, alumina, amorphous silica and mixtures thereof.  
     
     
         11 . The process of  claim 10  wherein said hydrogenation component comprises at least one Group VIII metal component.  
     
     
         12 . The process of  claim 11  wherein said binder is selected from the group consisting of zeolites, clays, silica, alumina, metal oxides, silica-alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania, silica-alumina-thoria, silica-alumina, zirconia, silica-alumina-magnesia, silica-magnesia-zirconia and mixtures thereof.  
     
     
         13 . A process according to  claim 10  wherein said zeolite component comprises a ZSM-48 zeolite.  
     
     
         14 . A process according to  claim 11  wherein Group VIII metal is a noble metal.  
     
     
         15 . A process according to  claim 14  wherein said noble metal is at least one of Pt and Pd.  
     
     
         16 . A process according to  claim 10  wherein in at least one of said stages said catalyst zeolite component comprises ZSM-48.  
     
     
         17 . A process comprising (a) producing synthesis gas comprising a mixture of H 2  and CO from natural gas, (b) contacting said synthesis gas with a cobalt Fischer-Tropsch hydrocarbon synthesis catalyst at reaction conditions effective for said H 2  and CO to react and form waxy hydrocarbons, including hydrocarbons boiling in the heavy lubricant oil range, (c) passing at least a portion of said waxy hydrocarbons to a hydrodewaxing upgrading facility in which said waxy hydrocarbons are (i) hydrodewaxed in the presence of a hydrodewaxing catalyst and hydrogen in a first hydrodewaxing stage, to produce an isomerate comprising a partially dewaxed heavy lubricant oil fraction and lower boiling hydrocarbons, (ii) separating said partially dewaxed heavy lubricant oil fraction and lower boiling hydrocarbons, and (ii) hydrodewaxing said separated heavy lubricant oil fraction in one or more successive hydrodewaxing stages, with interstage removal of hydrocarbons boiling below said heavy lubricant oil fraction, to form heavy lubricant base stock, wherein a hydrodewaxing catalyst comprising a zeolite component and a noble metal hydrogenating component is used in at least one hydrodewaxing stage.  
     
     
         18 . A process according to  claim 17  wherein said waxy hydrocarbons formed in (b) are not hydroprocessed prior to being passed to said hydrodewaxing upgrading facility.  
     
     
         19 . A process according to clam  18  wherein said heavy lubricant base stock has cloud and pour points lower than that of said heavy fraction in said wax.  
     
     
         20 . A process according to  claim 19  wherein said heavy lubricant base stock has an initial boiling point of at least 850° F. (454° C.).  
     
     
         21 . A process according to  claim 20  wherein said noble metal comprises at least one of Pt and Pd.  
     
     
         22 . A process according to  claim 21  wherein said base stock has been hydrofinished and optionally dehazed.  
     
     
         23 . A process according to  claim 17  wherein said zeolite component is selected from the group consisting of ZSM-23, ZSM-35, ZSM-48, ZSM-57, ZSM-22, silica-alumino phosphates, SSZ-32, zeolite beta mordenite, rare earth ion exchanged ferrierite, alumina, amorphous silica and mixtures thereof.  
     
     
         24 . The process of  claim 23  wherein said zeolite component is ZSM-48.  
     
     
         25 . A process according to  claim 23  wherein said hydrodewaxing catalyst comprising a ZSM-48 zeolite component and at least one of said Pt and Pd noble metal hydrogenating components is used in said first hydrodewaxing stage and at least one of said successive hydrodewaxing stages used to further hydrodewax said heavy lubricant oil fraction.  
     
     
         26 . A process according to  claim 25  wherein said base stock is combined with one or more lubricant additives to form a lubricant.  
     
     
         27 . A process according to  claim 26  wherein said heavy lubricant base stock has an end boiling point above 1050° F. (566° C.) and a cloud point no greater than 75° F. (24° C.).