Desulfurization and novel sorbents for same

Abstract

A sorbent composition is provided which can be used in the desulfurization of a hydrocarbon-containing fluid such as cracked gasoline or diesel fuel. The sorbent composition contains a support component and a promoter component with the promoter component being present as a skin on said support component. Such sorbent composition is prepared by a process of impregnating a support component with a promoter component, wherein the promoter component has been melted under a melting condition, followed by drying, calcining, and reducing to thereby provide the sorbent composition. A process for the removal of sulfur from a hydrocarbon stream, wherein the hydrocarbon stream is a combination of cracked gasoline and diesel fuel, is also disclosed.

What is claimed is:  
     
         1 . A process for the removal of sulfur from a hydrocarbon stream, wherein said hydrocarbon stream is a combination of cracked gasoline and diesel fuel, said process comprising: 
 (a) contacting said hydrocarbon stream with a composition comprising a zinc oxide, a silica-containing material, an aluminum-containing material selected from the group consisting of alumina, aluminate, and combinations thereof, and a promoter wherein at least a portion of said promoter is present as a reduced valence promoter and in an amount which will effect the removal of sulfur from said hydrocarbon stream in a desulfurization zone under conditions such that there is formed a desulfurized hydrocarbon stream and a sulfurized composition;    (b) separating said desulfurized hydrocarbon stream from said sulfurized composition thereby forming a separated desulfurized hydrocarbon stream and a separated sulfurized composition;    (c) regenerating at least a portion of said separated sulfurized composition in a regeneration zone so as to remove at least a portion of the sulfur contained therein and/or thereon thereby forming a regenerated composition;    (d) reducing said regenerated composition in an activation zone so as to provide a reduced composition having a reduced valence promoter content therein which will effect the removal of sulfur from a hydrocarbon stream when contacted with same; and thereafter    (e) returning at least a portion of said reduced composition to said desulfurization zone.    
     
     
         2 . A process in accordance with  claim 1 , wherein said diesel fuel is light cycle oil.  
     
     
         3 . A process in accordance with  claim 1  wherein said desulfurization in step (a) is carried out at a temperature in the range of from about 100° F. to about 1000° F. and a pressure in the range of from about 15 to about 1500 psia for a time sufficient to effect the removal of sulfur from said stream.  
     
     
         4 . A process in accordance with  claim 1  wherein said desulfurization in step (a) is carried out at a temperature in the range of from 400° F. to 900° F.  
     
     
         5 . A process in accordance with  claim 1  wherein said regeneration in step (c) is carried out at a temperature in the range of from about 100° F. to about 1500° F. and a pressure in the range of from about 10 to about 1500 psia for a time sufficient to effect the removal of at least a portion of the sulfur from said separated sulfurized composition.  
     
     
         6 . A process in accordance with  claim 1  wherein air is employed in step (c) as a regeneration agent in said regeneration zone.  
     
     
         7 . A process in accordance with  claim 1  wherein said regenerated composition from step (c) is subjected to reduction with hydrogen in step (d) in said reduction zone which is maintained at a temperature in the range of from about 100° F. to about 1500° F. and at a pressure in the range of from about 15 to about 1500 psia and for a period of time sufficient to effect a reduction of the valence of the promoter content of said regenerated composition.  
     
     
         8 . A process in accordance with  claim 1  wherein said separated sulfurized composition from step (b) is stripped prior to introduction into said regeneration zone in step (c).  
     
     
         9 . A process in accordance with  claim 1  wherein said regenerated composition from step (c) is stripped prior to introduction to said reduction zone in step (d).  
     
     
         10 . The cracked gasoline product of  claim 1 .  
     
     
         11 . The diesel fuel product of  claim 1.