Adsorbents for smoking articles comprising a non-volatile organic compound applied using a supercritical fluid

Abstract

A surface-modified adsorbent and a process for making a surface-modified adsorbent are provided. The process involves providing an adsorbent and a non-volatile organic compound to a vessel, adjusting the temperature and/or pressure to provide supercritical conditions for a supercritical fluid, and introducing the supercritical fluid into the vessel. The supercritical fluid dissolves the non-volatile organic compound, and impregnates the adsorbent with the non-volatile organic compound. The surface-modified adsorbent can be used, for example, in cut filler compositions, cigarette filters, and smoking articles. Methods for making cigarette filters, cigarettes and for smoking a cigarette comprising the surface-modified adsorbent are also provided. The surface-modified adsorbents can be used to remove one or more selected components from mainstream smoke, without removing other components, such as those that contribute to flavor.

What is claimed is:  
     
         1 . A process for making a surface-modified adsorbent, said process comprising: 
 (i) providing at least one adsorbent and at least one non-volatile organic compound to a vessel;    (ii) adjusting temperature and/or pressure to provide supercritical conditions in said vessel for a supercritical fluid; and    (iii) introducing the supercritical fluid into the vessel, such that the supercritical fluid dissolves the non-volatile organic compound, and wherein the supercritical fluid with the dissolved non-volatile organic compound impregnates the adsorbent to form a surface-modified adsorbent.    
     
     
         2 . The process of  claim 1 , wherein the adsorbent is selected from the group consisting of: adsorbent carbon, activated carbon, silica gel, alumina, polyester resins, zeolites or zeolite-like materials, and mixtures thereof.  
     
     
         3 . The process of  claim 2 , wherein the adsorbent is activated carbon.  
     
     
         4 . The process of  claim 3 , wherein the activated carbon comprises at least about 80% micropores.  
     
     
         5 . The process of  claim 3 , wherein the activated carbon has an average particle size from about 6 mesh to about 300 mesh.  
     
     
         6 . The process of  claim 3 , wherein the activated carbon has an average particle size from about 0.2 mm to about 1 mm.  
     
     
         7 . The process of  claim 1 , wherein the supercritical fluid is selected from the group consisting of: carbon dioxide, n-propane, n-butane, n-pentane, n-hexane, n-heptane, cyclohexane, ethanol, toluene, acetone, methyl acetate, diethyl ether, dichloromethane, dichlorodifluoromethane, trifluoromethane, carbon tetrachloride and mixtures thereof.  
     
     
         8 . The process of  claim 7 , wherein the supercritical fluid is carbon dioxide.  
     
     
         9 . The process of  claim 1 , wherein the non-volatile organic compound is selected from the group consisting of: alkenes, alkynes, cyclic and multicyclic hydrocarbons, aldehydes, ethers, amides, esters, fatty acids, fatty acid esters, and mixtures thereof.  
     
     
         10 . The process of  claim 9 , wherein the non-volatile organic compound is selected from the group consisting of: squalene, squalane, phytol, sucrose octa-palmitic acid ester, and mixtures thereof.  
     
     
         11 . The process of  claim 1 , wherein the non-volatile compound is capable of blocking pores in the adsorbent having an average size greater than about 20 Angstroms.  
     
     
         12 . The process of  claim 11 , wherein the non-volatile compound is capable of blocking pores in the adsorbent having an average size greater than about 10 Angstroms.  
     
     
         13 . A surface-modified adsorbent, produced by a process comprising: 
 (i) providing at least one adsorbent and at least one non-volatile organic compound to a vessel;    (ii) adjusting temperature and/or pressure to provide supercritical conditions in said vessel for a supercritical fluid; and    (iii) introducing the supercritical fluid into the vessel, such that the supercritical fluid dissolves the non-volatile organic compound, and wherein the supercritical fluid with the dissolved non-volatile organic compound impregnates the adsorbent to form a surface-modified adsorbent.    
     
     
         14 . The surface-modified adsorbent of  claim 13 , wherein the adsorbent is selected from the group consisting of: adsorbent carbon, activated carbon, silica gel, alumina, polyester resins, zeolite or zeolite-like materials, and mixtures thereof.  
     
     
         15 . A surface-modified adsorbent useful as a cigarette filtration agent wherein the adsorbent preferentially removes one or more selected components from tobacco smoke while allowing components that contribute to flavor to pass through the adsorbent, the adsorbent including pores impregnated with a non-volatile organic compound.  
     
     
         16 . The surface-modified adsorbent of  claim 15 , wherein the adsorbent comprises activated carbon having at least about 80% micropores.  
     
     
         17 . The surface-modified adsorbent of  claim 15 , wherein the adsorbent comprises activated carbon having an average particle size from about 6 mesh to about 300 mesh.  
     
     
         18 . The surface-modified adsorbent of  claim 15 , wherein the adsorbent comprises activated carbon having an average particle size from about 0.2 mm to about 1 mm.  
     
     
         19 . The surface-modified adsorbent of  claim 15 , wherein the adsorbent has been prepared by (i) providing at least one adsorbent and at least one non-volatile organic compound to a vessel; (ii) adjusting temperature and/or pressure to provide supercritical conditions in said vessel for a supercritical fluid; and (iii) introducing the supercritical fluid into the vessel, such that the supercritical fluid dissolves the non-volatile organic compound, and wherein the supercritical fluid with the dissolved non-volatile organic compound impregnates the adsorbent to form a surface-modified adsorbent.  
     
     
         20 . The surface-modified adsorbent of  claim 19 , wherein the supercritical fluid is selected from the group consisting of: carbon dioxide, n-propane, n-butane, n-pentane, n-hexane, n-heptane, cyclohexane, ethanol, toluene, acetone, methyl acetate, diethyl ether, dichloromethane, dichlorodifluoromethane, trifluoromethane, carbon tetrachloride and mixtures thereof.  
     
     
         21 . The surface-modified adsorbent of  claim 15 , wherein the non-volatile organic compound is selected from the group consisting of: alkenes, alkynes, cyclic or multicyclic hydrocarbons, aldehydes, ethers, amides, esters, fatty acids, fatty acid esters, and mixtures thereof.  
     
     
         22 . The surface-modified adsorbent of  claim 21 , wherein the non-volatile organic compound is selected from the group consisting of: squalene, squalane, phytol, sucrose octa-palmitic acid ester, and mixtures thereof.  
     
     
         23 . The surface-modified adsorbent of  claim 13 , wherein the non-volatile compound blocks pores in the adsorbent having an average size greater than about 20 Angstroms.  
     
     
         24 . The surface-modified adsorbent of  claim 23 , wherein the non-volatile compound blocks pores in the adsorbent having an average size greater than about 10 Angstroms.  
     
     
         25 . A smoking article comprising a surface-modified adsorbent according to  claim 13 .  
     
     
         26 . The smoking article of  claim 25 , wherein the smoking article is a cigarette.  
     
     
         27 . The smoking article of  claim 25 , wherein the surface-modified adsorbent is dispersed in smoking material.  
     
     
         28 . The smoking article of  claim 25 , wherein the surface-modified adsorbent is located in a filter.  
     
     
         29 . The smoking article of  claim 25 , wherein the adsorbent is selected from the group consisting of: adsorbent carbon, activated carbon, silica gel, alumina, polyester resins, zeolite and zeolite-like materials, and mixtures thereof.  
     
     
         30 . The smoking article of  claim 29 , wherein the adsorbent is activated carbon.  
     
     
         31 . The smoking article of  claim 30 , wherein the activated carbon comprises at least about 80% micropores.  
     
     
         32 . The smoking article of  claim 30 , wherein the activated carbon has an average particle size from about 6 mesh to about 300 mesh.  
     
     
         33 . The smoking article of  claim 30 , wherein the activated carbon has an average particle size from about 0.2 mm to about 1 mm.  
     
     
         34 . The smoking article of  claim 25 , comprising from about 10 mg to about 200 mg of the surface-modified adsorbent.  
     
     
         35 . A cigarette filter comprising a surface-modified adsorbent according to  claim 13 .  
     
     
         36 . The cigarette filter of  claim 35 , wherein the adsorbent is selected from the group consisting of: adsorbent carbon, activated carbon, silica gel, alumina, polyester resins, zeolite or zeolite-like materials, and mixtures thereof.  
     
     
         37 . The cigarette filter of  claim 36 , wherein the adsorbent is activated carbon.  
     
     
         38 . The cigarette filter of  claim 37 , wherein the activated carbon comprises at least about 80% micropores.  
     
     
         39 . The cigarette filter of  claim 37 , wherein the activated carbon has an average particle size from about 6 mesh to about 300 mesh.  
     
     
         40 . The cigarette filter of  claim 37 , wherein the activated carbon has an average particle size from about 0.2 mm to about 1 mm.  
     
     
         41 . The cigarette filter of  claim 35 , comprising from about 10 mg to about 200 mg of the surface-modified adsorbent.  
     
     
         42 . A cut filler composition comprising a surface-modified adsorbent according to  claim 13 .  
     
     
         43 . The cut filler composition of  claim 42 , wherein the adsorbent is selected from the group consisting of: adsorbent carbon, activated carbon, silica gel, alumina, polyester resins, zeolite and zeolite-like materials, and mixtures thereof.  
     
     
         44 . The cut filler composition of  claim 43 , wherein the adsorbent is activated carbon.  
     
     
         45 . The cut filler composition of  claim 44 , wherein the activated carbon comprises at least about 80% micropores.  
     
     
         46 . The cut filler composition of  claim 44 , wherein the activated carbon has an average particle size from about 10 mesh to about 20 mesh.  
     
     
         47 . The cut filler composition of  claim 44 , wherein the activated carbon has an average particle size from about 0.2 mm to about 1 mm.  
     
     
         48 . A method of making a cigarette filter, said method comprising: 
 (i) providing a surface-modified adsorbent according to  claim 13 , and    (ii) incorporating the surface-modified adsorbent into a cigarette filter.    
     
     
         49 . A method of making a cigarette, said method comprising: 
 (i) providing a cut filler to a cigarette making machine to form a tobacco rod;    (ii) placing a paper wrapper around the tobacco rod;    (iii) providing a cigarette filter according to  claim 35;  and    (iv) attaching the cigarette filter to the tobacco rod to form the cigarette.    
     
     
         50 . A method of making a cigarette, said method comprising: 
 (i) adding a surface-modified adsorbent according to  claim 13  to a cut filler;    (ii) providing the cut filler comprising the surface-modified adsorbent to a cigarette making machine to form a tobacco rod; and    (iii) placing a paper wrapper around the tobacco rod to form the cigarette.    
     
     
         51 . A method of smoking the smoking article of  claim 26 , said method comprising lighting the cigarette to form smoke and drawing the smoke through the cigarette, wherein during the smoking of the cigarette, the surface-modified adsorbent preferentially removes one or more selected components from mainstream smoke.