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 is disclosed.