Patent ID: 7923593

Claim:
A process for producing a middle distillate, comprising: a. reacting an isobutane stream with a process stream containing butene under alkylation conditions wherein the isobutane and butene are alkylated to produce an alkylate product in the presence of a chloroaluminate ionic liquid having the general formula RR′ R″ N H + Al 2 Cl 7 − , wherein RR′ and R″ are alkyl groups containing 1 to 12 carbons; b. adjusting over time a halide containing additive during the reacting step to improve the selectivity for the middle distillate; and c. separating out the middle distillate from the alkylate product, wherein the separated middle distillate fraction is from 20 wt % or higher of the total alkylate product.