Patent ID: 7553999

Claim:
A process for producing alkylate comprising contacting a first hydrocarbon stream comprising at least one olefin having from 2 to 6 carbon atoms which contains 1-butene with an isomerization catalyst under conditions favoring the isomerization of 1-butene to 2-butene so the isomerized stream contains a greater concentration of 2-butene than the first hydrocarbon stream and contacting the isomerized stream and a second hydrocarbon stream comprising at least one isoparaffin having from 3 to 6 carbon atoms with an acidic ionic liquid catalyst under alkylation conditions to produce an alkylate stream; where the acidic ionic acidic ionic liquid is a chloroaluminate ionic liquid prepared by mixing aluminum trichloride (AlCl 3 ) and a hydrocarbyl substituted pyridinium halide, a hydrocarbyl substituted imidazolium halide, trialkylammonium hydrohalide or tetraalkylammonium halide of the general formulas A, B, C and D, respectively, where R═H, methyl, ethyl, propyl, butyl, pentyl or hexyl group and X is a halide and preferably a chloride, 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, and R 3 , R 4 , and R 5 and R 6 =methyl, ethyl, propyl, butyl, pentyl or hexyl group and where R 3 , R 4 , R 5 and R 6 may or may not be the same; and wherein the acidic ionic liquid catalyst further comprises an alkyl halide.