Isomerization process using metal-modified small crystallite mtt molecular sieve

Abstract

Dewaxing a hydrocarbon feed by isomerizing feed with catalyst comprising small crystallite molecular sieve having MTT framework, the catalyst containing at least one metal selected from the group consisting of Ca, Cr, Mg, La, Na, Pr, Sr, K and Nd, and at least one Group VIII metal. A dewaxing method to produce products boiling at 343° C. (650° F.) or higher with low pour points and high viscosity indexes wherein the line fit to the chart of the pour points and the viscosity indexes has a slope of zero or less. A dewaxing process, comprising isomerization dewaxing feed with a viscosity at 100° C. of 2.5 mm 2 /s or greater over a metal-modified molecular sieve to produce products with low pour points and high viscosity indexes; the line fit to the chart of the pour points and the viscosity indexes has a slope of zero or less; and wherein the yield of products is high.

1 . A process for dewaxing a hydrocarbon feed to produce an isomerized product, the feed including straight chain and slightly branched paraffins having 10 or more carbon atoms, comprising contacting the feed under isomerization conditions in the presence of hydrogen with a catalyst comprising a molecular sieve having MTT framework topology and having a crystallite diameter of about 200 to about 400 Angstroms in the longest direction, the catalyst containing at least one metal selected from the group consisting of Ca, Cr, Mg, La, Na, Pr, Sr, K and Nd and at least one Group VIII metal. 
     
     
         2 . The process of  claim 1  wherein the MTT molecular sieve is selected from the group consisting of SSZ-32, ZSM-23, EU-13, ISI-4, and KZ-1. 
     
     
         3 . The process of  claim 1 , wherein said feed is selected from the group consisting of hydrotreated or hydrocracked gas oils, hydrotreated lube oil raffinates, bright stocks, lubricating oil stocks, synthetic oils, foots oils, Fischer-Tropsch synthesis oils, high pour point polyolefins, normal alphaolefin waxes, slack waxes, deoiled waxes, microcrystalline waxes, and mixtures thereof. 
     
     
         4 . The process of  claim 1 , wherein Group VIII metals are selected from the group consisting of platinum and palladium, and mixtures thereof. 
     
     
         5 . The process of  claim 1  wherein said contacting is carried out at a temperature of from 232-427° C. (450-800° F.), and a pressure in the range from about 103.4 kPa gauge (15 psig) to about 20,685 kPa gauge (3000 psig). 
     
     
         6 . The process of  claim 5  wherein said pressure is in the range from about 689.5 kPa gauge (100 psig) to about 17927 kPa gauge (2600 psig). 
     
     
         7 . The process of  claim 5 , wherein the liquid hourly space velocity during contacting is from about 0.1 to about 20. 
     
     
         8 . The process of  claim 7 , wherein the liquid hourly space velocity is from 0.5 to about 5. 
     
     
         9 . The process of  claim 1  wherein the hydrocarbon feed is hydrotreated prior to isomerization at a temperature in the range from 163 to 427° C. (325 to 800° F.). 
     
     
         10 . The process of  claim 1 , further comprising a hydrofinishing step following isomerization. 
     
     
         11 . The process of  claim 10  wherein hydrofinishing is carried out at a temperature in the range from about 163 to about 310° C. (325 to about 590° F.) and a pressure in the range from about 2068 kPa gauge (300 psig) to about 20,685 kPa gauge (3000 psig). 
     
     
         12 . A dewaxing method, comprising isomerization dewaxing a hydrocarbon feed having at least 5 wt % wax over a catalyst to produce two or more isomerized products boiling at 343° C. (650° F.) or higher, each, isomerized product having:
 a. a pour point between 0 and −30° C., and   b. a corresponding viscosity index of 95 or higher;   
       wherein a line fit to a chart of the pour points on an x-axis and the viscosity indexes on a y-axis has a slope of the line for y of zero or less. 
     
     
         13 . The dewaxing method of  claim 12 , wherein the hydrocarbon feed has at least 10 wt % wax. 
     
     
         14 . The dewaxing method of  claim 12 , wherein the hydrocarbon feed has a kinematic viscosity at 100° C. of 2.5 mm 2 /s or greater. 
     
     
         15 . The dewaxing method of  claim 12 , wherein the catalyst comprises a molecular sieve having MTT framework topology and having a crystallite diameter of about 200 to about 400 Angstroms in the longest direction. 
     
     
         16 . The dewaxing method of  claim 15 , wherein the catalyst further comprises at least one metal selected from the group consisting of Ca, Cr, Mg, La, Na, Pr, Sr, K and Nd. 
     
     
         17 . The dewaxing method of  claim 16 , wherein the catalyst further comprises at least one Group VIII metal. 
     
     
         18 . The dewaxing method of  claim 12 , wherein the two or more isomerized products boiling at 343° C. (650° F.) or higher have a corresponding viscosity index of 104 or higher. 
     
     
         19 . The dewaxing method of  claim 12 , wherein a yield of the two or more isomerized products boiling at 343° C. (650° F.) or higher is 90 wt % or greater based on the feed. 
     
     
         20 . The dewaxing method of  claim 19 , wherein the yield is 94 wt % or greater. 
     
     
         21 . The dewaxing method of  claim 12 , wherein the slope of the line is less than −0.05. 
     
     
         22 . A dewaxing process, comprising isomerization dewaxing a hydrocarbon feed having at least 5 wt % wax over a catalyst to produce two or more isomerized products boiling at 343° C. (650° F.) or higher, each isomerized product having:
 a. a pour point between 0 and −30° C., and   b. a corresponding viscosity index of 95 or higher;   
       wherein a line fit to a chart of the pour points on an x-axis and the viscosity indexes on a y-axis has a slope of the line for y of zero or less; and wherein the yield of the two or more isomerized products boiling at 343° C. (650° F.) or higher is 90 wt % or greater based on the feed. 
     
     
         23 . The dewaxing process of  claim 22 , wherein the molecular sieve has MTT framework topology. 
     
     
         24 . The dewaxing process of  claim 22 , wherein the molecular sieve has a crystallite size of about 200-400 Angstroms.