Ionic liquid catalyst alkylation using a loop reactor

Abstract

Provided is a process for producing low volatility, high quality gasoline blending components which comprises recirculation of at least a portion of a recovered stream comprising primarily isoparaffins. Recirculation of the stream allows for an enhanced I/O ratio and a more cost effective process.

1 . A process for the production of low volatility, high quality gasoline blending components comprising:
 (a) providing at least one olefin feed stream comprising olefins;   (b) providing at least one isoparaffin feed stream comprising isoparaffins;   (c) contacting the at least one olefin feed stream with the at least one isoparaffin feed stream in the presence of an ionic liquid catalyst in an alkylation zone under alkylation conditions to provide at least one product stream; and   (d) recirculating to the alkylation zone a stream comprised of primarily isoparaffin.   
     
     
         2 . The process according to  claim 1 , wherein the olefin feed stream comprise at least one olefin selected from the group consisting of ethylene, propylene, butene, pentene, and mixtures thereof. 
     
     
         3 . The process according to  claim 1 , wherein the isoparaffin feed stream comprise at least one isoparaffin selected from the group consisting of isobutane, isopentane, and mixtures thereof. 
     
     
         4 . The process according to  claim 1 , further comprising:
 passing a product stream through at least one heat exchanger; and   removing heat from the product stream.   
     
     
         5 . The process according to  claim 1 , wherein the stream comprised of primarily isoparaffin is separated from effluent obtained from the contacting in step (c). 
     
     
         6 . The process according to  claim 1 , wherein the stream comprised primarily of isoparaffin is condensed from vaporous overhead in a horizontal reactor in which the contacting in step (c) occurs. 
     
     
         7 . The process according to  claim 1 , wherein the ionic liquid catalyst is selected from the group consisting of:
 a chloroaluminate ionic liquid catalyst comprising a hydrocarbyl substituted pyridinium halide or a hydrocarbyl substituted imidazolium halide of the general formulas A and B, respectively;   a chloroaluminate ionic liquid catalyst comprising an alkyl substituted pyridinium halide or an alkyl substituted imidazolium halide of the general formulas A and B, respectively;   
       
         
           
           
               
               
           
         
       
       and mixtures thereof, 
       where R═H, methyl, ethyl, propyl, butyl, pentyl or hexyl group and X is a haloaluminate and preferably a chloroaluminate, and R 1  and R 2 ═H, methyl, ethyl, propyl, butyl, pentyl, or hexyl group and where R 1  and R 2  may or may not be the same. 
     
     
         8 . The process according to  claim 7 , wherein the ionic liquid catalyst is selected from the group consisting of 1-butyl-4-methyl-pyridinium chloroaluminate (BMP), 1-butyl-pyridinium chloroaluminate (BP), 1-butyl-3-methyl-imidazolium chloroaluminate (BMIM), 1-H-pyridinium chloroaluminate (HP), and N-butylpyridinium chloroaluminate. 
     
     
         9 . The process according to  claim 7 , wherein the catalyst further comprises an HCI co-catalyst. 
     
     
         10 . The process according to  claim 1 , wherein there are multiple injections of olefin into the alkylation zone. 
     
     
         11 . The process according to  claim 1 , wherein there are multiple injections of isoparaffin into the alkylation zone. 
     
     
         12 . The process according to  claim 1 , wherein the I/O ratio of newly added reactants injected into the alkylation zone is in the range of from 6:1 to 10:1.