Oligomerization of alpha olefins in the presence of carboxylic acids

Abstract

In process for the oligomerization of an alphaolefin, a carboxylic acid modifier, such as acetic acid, is used to increase the amount of trimer and tetramer in the product.

1 - 9 . (canceled)  
     
     
         10 . An improved solvent-free oligomerization process to produce a polyalphaolefin product comprising: 
 a) charging to a reaction zone a feed mixture comprising an alpha olefin;    b) contacting the feed mixture with a catalyst complex comprising boron trifluoride and an alcohol promoter; and    c) providing a concentration of a modifier comprising a carboxylic acid within the reaction zone;    wherein the concentration of the carboxylic acid is sufficient to increase the yield of trimer and tetramer in the polyalphaolefin product as compared to the yield when the carboxylic acid is not present.    
     
     
         11 . The process of  claim 10  wherein the carboxylic acid contains from 2 to 10 carbon atoms.  
     
     
         12 . The process of  claim 10  wherein the concentration of the carboxylic acid ranges from about 0.08 mole percent to about 2.0 mole percent based on the alpha olefin of the feed mixture.  
     
     
         13 . The process of  claim 12  wherein the concentration of the carboxylic acid ranges from 0.16 mole percent to 0.35 mole percent based on the alpha olefin of the feed mixture.  
     
     
         14 . The process of  claim 10  wherein the reaction zone is maintained at a temperature in excess of 30° C.  
     
     
         15 . The process of  claim 14  wherein the reaction zone is maintained at a temperature in the range of from 40° C. to 150° C.  
     
     
         16 . The process of  claim 15  wherein the alpha olefin is selected from monounsaturated alpha olefins having from 3 to 22 carbon atoms.  
     
     
         17 . The process of  claim 16  wherein the alpha olefin contains from 3 to 14 carbon atoms.  
     
     
         18 . The process of  claim 17  wherein the alpha olefin is selected from the group consisting of propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-dodecene, and 1-tetradecene.  
     
     
         19 . An improved solvent-free oligomerization process comprising: 
 a) contacting an alpha olefin, a catalyst complex, and a carboxylic acid modifier; and    b) oligomerizing the alpha olefin to produce a polyalphaolefin product;    wherein the catalyst complex comprises boron trifluoride and an alcohol promoter; and    wherein the carboxylic acid modifier is present in a concentration sufficient to increase the yield of trimer and tetramer in the polyalphaolefin product as compared to the yield when the carboxylic acid is not present.    
     
     
         20 . A polyalphaolefin product produced by the process comprising: 
 a) charging to a reaction zone a feed mixture comprising an alpha olefin;    b) contacting the feed mixture with a catalyst complex comprising boron trifluoride and an alcohol promoter;    c) providing a concentration of a modifier comprising a carboxylic acid within the reaction zone; and    d) withdrawing from the reaction zone the polyalphaolefin product;    wherein the concentration of the carboxylic acid is sufficient to significantly increase the yield of trimer and tetramer in the polyalphaolefin product withdrawn from the reaction zone as compared to the yield when the carboxylic acid is not present.    
     
     
         21 . The product of  claim 20  wherein the significant increase in the yield of trimer and tetramer in the polyalphaolefin product withdrawn from the reaction zone is at least 20 percent.