Low temperature sorbents for removal of sulfur compounds from fluid feed streams

Abstract

A sorbent material is provided comprising a material reactive with sulfur, a binder unreactive with sulfur and an inert material, wherein the sorbent absorbs the sulfur at temperatures between 30 and 200° C. Sulfur absorption capacity as high as 22 weight percent has been observed with these materials.

The embodiment of the invention in which an exclusive property or privilege is claimed is defined as follows:  
     
         1 . A material for absorbing sulfur at between 30° C. and 200° C., the material comprising: 
 a) a compound reactive with sulfur; and  
 b) an inert substance combined with the compound.  
 
     
     
         2 . The material as recited in  claim 1  wherein the inert substance is a porous substance which is impregnated with the compound.  
     
     
         3 . The material as recited in  claim 2  wherein the inert substance is approximately 100 microns to 4 millimeters in size.  
     
     
         4 . The material as recited in  claim 1  wherein the compound and the inert substance is mixed with a binder.  
     
     
         5 . The material as recited in  claim 2  wherein the inert substance is a porous substance selected from the group consisting of titania, silica, alumina, alumino silicate, zirconia, zeolites, carbon or a combination thereof.  
     
     
         6 . The material as recited in  claim 1  wherein the compound is rubidium hydroxide and the absorption occurs at 30° C.  
     
     
         7 . The material as recited in  claim 1  wherein the compound is copper hydroxide and the absorption occurs at between 30° C. and 200° C.  
     
     
         8 . The material as recited in  claim 1  wherein the material contains from 2 to 80 weight percent of the inert substance.  
     
     
         9 . The material as recited in  claim 1  wherein the inert substance is comprised of a first portion and a second portion.  
     
     
         10 . The material as recited in  claim 9  wherein the first portion is a diluent selected from the group consisting of titanium oxide, calcium sulfate, calcium phosphate, calcium silicate, magnesium sulfate, zinc silicate, zinc aluminate, and alumino silicate.  
     
     
         11 . The material as recited in  claim 9  wherein the second portion of the inert substance comprises up to 40 weight percent of the material and the second portion has particle sizes larger than particle sizes of the compound.  
     
     
         12 . The material as recited in  claim 9  wherein at least two weight percent of the second portion has particles that are twice as large as particles comprising the compound.  
     
     
         13 . The material as recited in  claim 8  wherein the first portion is a diluent and wherein approximately 2 to 30 weight percent of the second portion has particles that are twice as large as particles comprising the compound.  
     
     
         14 . The material as recited in  claim 9  wherein the second portion is a granular substrate selected from the group consisting of silica gel, silica, alumina, alumina gel, titania gel, calcium sulfate, zinc silicate, zinc aluminate, sand or combinations thereof.  
     
     
         15 . The material as recited in  claim 1  wherein the material contains from 30 to 70 weight percent of the compound.  
     
     
         16 . The material as recited in  claim 4  wherein the binder is an organic compound selected from the group consisting of hydroxypropyl methyl cellulose, molasses, starch, polyvinyl acetate, cellulose, hydropropyl cellulose, lignin sulfonate, or combinations thereof.  
     
     
         17 . The material as recited in  claim 4  wherein the binder is an inorganic compound selected from the group consisting of bentonite, kaolinite, alumino silicates, calcium sulfate, cement, or mixtures thereof.  
     
     
         18 . A material for absorbing sulfur, the material comprising: 
 a) copper hydroxide;    b) an inert material present at a weight percent of the material of approximately 7 to 12 percent;    c) a binder material present at approximately 8 to 12 weight percent of the material; and    d) a diluent material present at approximately 15 to 25 weight percent of the material.    
     
     
         19 . The material as recited in  claim 18  wherein the inert material is silica gel and half of the silica gel is present as particles at 35-60 mesh while the other half of the silica gel is present as particles at 100-200 mesh.  
     
     
         20 . The material as recited in  claim 18  wherein the binder is bentonite.  
     
     
         21 . The material as recited in  claim 18  wherein the diluent is titanium dioxide.  
     
     
         22 . A method for producing a sorbent capable of removing sulfur from a gas stream at temperatures ranging from 30° C. to 200° C., the method comprising: 
 a) combining a sulfur reactive compound with an inert material and a binder to create a homogenous mixture;  
 b) pelletizing the mixture; and  
 c) calcining the pelletized mixture at a temperature sufficient to solidify the mixture.  
 
     
     
         23 . The method as recited in  claim 22  wherein the sulfur reactive compound is an oxygen containing compound selected from the group consisting of copper hydroxide, copper (II) oxide, iron (III) hydroxide, potassium bicarbonate, rubidium hydroxide, zinc oxide, zinc oxide hydrate, lithium hydroxide, sodium peroxide, and ferric oxide.  
     
     
         24 . The method as recited in  claim 22  wherein the inert material is a granular substrate selected from the group consisting of silica gel, silica, alumina, alumina gel, titania gel, calcium sulfate, zinc silicate, zinc aluminate, sand or combinations thereof.  
     
     
         25 . The method as recited in  claim 22  wherein approximately 2 to 30 weight percent of the inert material has particles twice as large as particles comprising the compound.  
     
     
         26 . The method as recited in  claim 22  wherein the compound comprises between 30 to 70 weight percent of the sorbent.